1
|
Gamberucci A, Nanni C, Pierantozzi E, Serano M, Protasi F, Rossi D, Sorrentino V. TAM-associated CASQ1 mutants diminish intracellular Ca 2+ content and interfere with regulation of SOCE. J Muscle Res Cell Motil 2024:10.1007/s10974-024-09681-9. [PMID: 39126637 DOI: 10.1007/s10974-024-09681-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2024] [Accepted: 07/31/2024] [Indexed: 08/12/2024]
Abstract
Tubular aggregate myopathy (TAM) is a rare myopathy characterized by muscle weakness and myalgia. Muscle fibers from TAM patients show characteristic accumulation of membrane tubules that contain proteins from the sarcoplasmic reticulum (SR). Gain-of-function mutations in STIM1 and ORAI1, the key proteins participating in the Store-Operated Ca2+ Entry (SOCE) mechanism, were identified in patients with TAM. Recently, the CASQ1 gene was also found to be mutated in patients with TAM. CASQ1 is the main Ca2+ buffer of the SR and a negative regulator of SOCE. Previous characterization of CASQ1 mutants in non-muscle cells revealed that they display altered Ca2+dependent polymerization, reduced Ca2+storage capacity and alteration in SOCE inhibition. We thus aimed to assess how mutations in CASQ1 affect calcium regulation in skeletal muscles, where CASQ1 is naturally expressed. We thus expressed CASQ1 mutants in muscle fibers from Casq1 knockout mice, which provide a valuable model for studying the Ca2+ storage capacity of TAM-associated mutants. Moreover, since Casq1 knockout mice display a constitutively active SOCE, the effect of CASQ1 mutants on SOCE inhibition can be also properly examined in fibers from these mice. Analysis of intracellular Ca2+ confirmed that CASQ1 mutants have impaired ability to store Ca2+and lose their ability to inhibit skeletal muscle SOCE; this is in agreement with the evidence that alterations in Ca2+entry due to mutations in either STIM1, ORAI1 or CASQ1 represents a hallmark of TAM.
Collapse
Affiliation(s)
- Alessandra Gamberucci
- Department of Molecular and Developmental Medicine, University of Siena, Siena, I-53100, Italy
| | - Claudio Nanni
- Department of Molecular and Developmental Medicine, University of Siena, Siena, I-53100, Italy
| | - Enrico Pierantozzi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, I-53100, Italy
| | - Matteo Serano
- Department of Molecular and Developmental Medicine, University of Siena, Siena, I-53100, Italy
| | - Feliciano Protasi
- Center for Advanced Studies and Technology, CAST, University G. d'Annunzio of Chieti-Pescara, Chieti, I-66100, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d'Annunzio of Chieti-Pescara, Chieti, I-66100, Italy
| | - Daniela Rossi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, I-53100, Italy
- Interdepartmental Program of Molecular Diagnosis and Pathogenetic Mechanisms of Rare Genetic Diseases, Azienda Ospedaliero Universitaria Senese, Siena, I-53100, Italy
| | - Vincenzo Sorrentino
- Department of Molecular and Developmental Medicine, University of Siena, Siena, I-53100, Italy.
- Interdepartmental Program of Molecular Diagnosis and Pathogenetic Mechanisms of Rare Genetic Diseases, Azienda Ospedaliero Universitaria Senese, Siena, I-53100, Italy.
| |
Collapse
|
2
|
Serrano-Novillo C, Estadella I, Navarro-Pérez M, Oliveras A, de Benito-Bueno A, Socuéllamos PG, Bosch M, Coronado MJ, Sastre D, Valenzuela C, Soeller C, Felipe A. Routing of Kv7.1 to endoplasmic reticulum plasma membrane junctions. Acta Physiol (Oxf) 2024; 240:e14106. [PMID: 38282556 DOI: 10.1111/apha.14106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/21/2023] [Accepted: 01/01/2024] [Indexed: 01/30/2024]
Abstract
AIM The voltage-gated Kv7.1 channel, in association with the regulatory subunit KCNE1, contributes to the IKs current in the heart. However, both proteins travel to the plasma membrane using different routes. While KCNE1 follows a classical Golgi-mediated anterograde pathway, Kv7.1 is located in endoplasmic reticulum-plasma membrane junctions (ER-PMjs), where it associates with KCNE1 before being delivered to the plasma membrane. METHODS To characterize the channel routing to these spots we used a wide repertoire of methodologies, such as protein expression analysis (i.e. protein association and biotin labeling), confocal (i.e. immunocytochemistry, FRET, and FRAP), and dSTORM microscopy, transmission electron microscopy, proteomics, and electrophysiology. RESULTS We demonstrated that Kv7.1 targeted ER-PMjs regardless of the origin or architecture of these structures. Kv2.1, a neuronal channel that also contributes to a cardiac action potential, and JPHs, involved in cardiac dyads, increased the number of ER-PMjs in nonexcitable cells, driving and increasing the level of Kv7.1 at the cell surface. Both ER-PMj inducers influenced channel function and dynamics, suggesting that different protein structures are formed. Although exhibiting no physical interaction, Kv7.1 resided in more condensed clusters (ring-shaped) with Kv2.1 than with JPH4. Moreover, we found that VAMPs and AMIGO, which are Kv2.1 ancillary proteins also associated with Kv7.1. Specially, VAP B, showed higher interaction with the channel when ER-PMjs were stimulated by Kv2.1. CONCLUSION Our results indicated that Kv7.1 may bind to different structures of ER-PMjs that are induced by different mechanisms. This variable architecture can differentially affect the fate of cardiac Kv7.1 channels.
Collapse
Affiliation(s)
- Clara Serrano-Novillo
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Irene Estadella
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - María Navarro-Pérez
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Anna Oliveras
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- Berlin Institute of Medical Systems Biology (BIMSB), Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | | | - Paula G Socuéllamos
- Instituto de Investigaciones Biomédicas Alberto Sols CSIC-UAM, Madrid, Spain
| | - Manel Bosch
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- Scientific and Technological Centers (CCiTUB), Universitat de Barcelona, Barcelona, Spain
| | - María José Coronado
- Unidad de Microscopía Confocal, Instituto de Investigación Sanitaria Puerta de Hierro-Segovia de Arana (IDIPHISA), Hospital Universitario Puerta de Hierro, Madrid, Spain
| | - Daniel Sastre
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- Department of Anesthesiology, Pharmacology and Therapeutics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carmen Valenzuela
- Instituto de Investigaciones Biomédicas Alberto Sols CSIC-UAM, Madrid, Spain
| | | | - Antonio Felipe
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| |
Collapse
|
3
|
Marabelli C, Santiago DJ, Priori SG. The Structural-Functional Crosstalk of the Calsequestrin System: Insights and Pathological Implications. Biomolecules 2023; 13:1693. [PMID: 38136565 PMCID: PMC10741413 DOI: 10.3390/biom13121693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/14/2023] [Accepted: 11/21/2023] [Indexed: 12/24/2023] Open
Abstract
Calsequestrin (CASQ) is a key intra-sarcoplasmic reticulum Ca2+-handling protein that plays a pivotal role in the contraction of cardiac and skeletal muscles. Its Ca2+-dependent polymerization dynamics shape the translation of electric excitation signals to the Ca2+-induced contraction of the actin-myosin architecture. Mutations in CASQ are linked to life-threatening pathological conditions, including tubular aggregate myopathy, malignant hyperthermia, and Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT). The variability in the penetrance of these phenotypes and the lack of a clear understanding of the disease mechanisms associated with CASQ mutations pose a major challenge to the development of effective therapeutic strategies. In vitro studies have mainly focused on the polymerization and Ca2+-buffering properties of CASQ but have provided little insight into the complex interplay of structural and functional changes that underlie disease. In this review, the biochemical and structural natures of CASQ are explored in-depth, while emphasizing their direct and indirect consequences for muscle Ca2+ physiology. We propose a novel functional classification of CASQ pathological missense mutations based on the structural stability of the monomer, dimer, or linear polymer conformation. We also highlight emerging similarities between polymeric CASQ and polyelectrolyte systems, emphasizing the potential for the use of this paradigm to guide further research.
Collapse
Affiliation(s)
- Chiara Marabelli
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy;
- Laboratory of Molecular Cardiology, IRCCS ICS Maugeri, 27100 Pavia, Italy
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain;
| | - Demetrio J. Santiago
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain;
| | - Silvia G. Priori
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy;
- Laboratory of Molecular Cardiology, IRCCS ICS Maugeri, 27100 Pavia, Italy
- Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), 28029 Madrid, Spain;
| |
Collapse
|
4
|
Zhang K, Zhang G, Duan H, Li Q, Huang K, Xu L, Yang H, Luo Y. CASQ1-related myopathy: The first report from China and the literature review. Clin Case Rep 2022; 10:e6689. [PMID: 36514469 PMCID: PMC9731158 DOI: 10.1002/ccr3.6689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/31/2022] [Accepted: 11/11/2022] [Indexed: 12/13/2022] Open
Abstract
Calsequestrin 1 (CASQ1) is the most crucial Ca2+ binding protein localized in the sarcoplasmic reticulum (SR) of skeletal muscle. With high capacity and low affinity for Ca2+, CASQ1 plays a significant role in maintaining a large amount of Ca2+ necessary for muscle contraction. However, only five mutations in CASQ1 have been identified to date. Here, we report a 42-year-old Chinese female patient who presented with a 12 years history of slowly progressive upper limb weakness, predominantly affecting distal muscles, which was uncommon comparing to other CASQ1-related patients. Next-generation sequencing (NGS) analysis revealed a novel heterozygous mutation (c.766G > A, p.Val256Met) in CASQ1. Functional studies confirmed the likely pathogenicity of this variant. Muscle histopathology revealed rare optically empty vacuoles in myofibers and atypical eosinophilic granules in the cytoplasm, which has not been observed before. We also performed a literature review on all the pathogenic mutations in CASQ1 and summarized their genetic and clinical characteristics. This is the first report on CASQ1-related myopathy from China, further expanding the mutation spectrum of CASQ1 gene and provides new insights into the function of CASQ1.
Collapse
Affiliation(s)
- Kai‐Yue Zhang
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Geng‐Jian Zhang
- Department of DermatologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Hui‐Qian Duan
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Qiu‐Xiang Li
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Kun Huang
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Li‐Qun Xu
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Huan Yang
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| | - Yue‐Bei Luo
- Department of Neurology, Xiangya HospitalCentral South UniversityChangshaChina
| |
Collapse
|
5
|
Protasi F, Girolami B, Serano M, Pietrangelo L, Paolini C. Ablation of Calsequestrin-1, Ca 2+ unbalance, and susceptibility to heat stroke. Front Physiol 2022; 13:1033300. [PMID: 36311237 PMCID: PMC9598425 DOI: 10.3389/fphys.2022.1033300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/20/2022] [Indexed: 12/05/2022] Open
Abstract
Introduction: Ca2+ levels in adult skeletal muscle fibers are mainly controlled by excitation-contraction (EC) coupling, a mechanism that translates action potentials in release of Ca2+ from the sarcoplasmic reticulum (SR) release channels, i.e. the ryanodine receptors type-1 (RyR1). Calsequestrin (Casq) is a protein that binds large amounts of Ca2+ in the lumen of the SR terminal cisternae, near sites of Ca2+ release. There is general agreement that Casq is not only important for the SR ability to store Ca2+, but also for modulating the opening probability of the RyR Ca2+ release channels. The initial studies: About 20 years ago we generated a mouse model lacking Casq1 (Casq1-null mice), the isoform predominantly expressed in adult fast twitch skeletal muscle. While the knockout was not lethal as expected, lack of Casq1 caused a striking remodeling of membranes of SR and of transverse tubules (TTs), and mitochondrial damage. Functionally, CASQ1-knockout resulted in reduced SR Ca2+ content, smaller Ca2+ transients, and severe SR depletion during repetitive stimulation. The myopathic phenotype of Casq1-null mice: After the initial studies, we discovered that Casq1-null mice were prone to sudden death when exposed to halogenated anaesthetics, heat and even strenuous exercise. These syndromes are similar to human malignant hyperthermia susceptibility (MHS) and environmental-exertional heat stroke (HS). We learned that mechanisms underlying these syndromes involved excessive SR Ca2+ leak and excessive production of oxidative species: indeed, mortality and mitochondrial damage were significantly prevented by administration of antioxidants and reduction of oxidative stress. Though, how Casq1-null mice could survive without the most important SR Ca2+ binding protein was a puzzling issue that was not solved. Unravelling the mystery: The mystery was finally solved in 2020, when we discovered that in Casq1-null mice the SR undergoes adaptations that result in constitutively active store-operated Ca2+ entry (SOCE). SOCE is a mechanism that allows skeletal fibers to use external Ca2+ when SR stores are depleted. The post-natal compensatory mechanism that allows Casq1-null mice to survive involves the assembly of new SR-TT junctions (named Ca2+ entry units) containing Stim1 and Orai1, the two proteins that mediate SOCE.
Collapse
Affiliation(s)
- Feliciano Protasi
- Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
- Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
| | - Barbara Girolami
- Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
- Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
| | - Matteo Serano
- Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
- Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
| | - Laura Pietrangelo
- Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
- Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
| | - Cecilia Paolini
- Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
- Department of Neuroscience, Imaging and Clinical Sciences, University G. d’Annunzio of Chieti-Pescara, Chieti, Italy
| |
Collapse
|
6
|
Rossi D, Catallo MR, Pierantozzi E, Sorrentino V. Mutations in proteins involved in E-C coupling and SOCE and congenital myopathies. J Gen Physiol 2022; 154:213407. [PMID: 35980353 PMCID: PMC9391951 DOI: 10.1085/jgp.202213115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 07/15/2022] [Accepted: 07/21/2022] [Indexed: 11/24/2022] Open
Abstract
In skeletal muscle, Ca2+ necessary for muscle contraction is stored and released from the sarcoplasmic reticulum (SR), a specialized form of endoplasmic reticulum through the mechanism known as excitation–contraction (E-C) coupling. Following activation of skeletal muscle contraction by the E-C coupling mechanism, replenishment of intracellular stores requires reuptake of cytosolic Ca2+ into the SR by the activity of SR Ca2+-ATPases, but also Ca2+ entry from the extracellular space, through a mechanism called store-operated calcium entry (SOCE). The fine orchestration of these processes requires several proteins, including Ca2+ channels, Ca2+ sensors, and Ca2+ buffers, as well as the active involvement of mitochondria. Mutations in genes coding for proteins participating in E-C coupling and SOCE are causative of several myopathies characterized by a wide spectrum of clinical phenotypes, a variety of histological features, and alterations in intracellular Ca2+ balance. This review summarizes current knowledge on these myopathies and discusses available knowledge on the pathogenic mechanisms of disease.
Collapse
Affiliation(s)
- Daniela Rossi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.,Interdepartmental Program of Molecular Diagnosis and Pathogenetic Mechanisms of Rare Genetic Diseases, Azienda Ospedaliero Universitaria Senese, Siena, Italy
| | - Maria Rosaria Catallo
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Enrico Pierantozzi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Vincenzo Sorrentino
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy.,Interdepartmental Program of Molecular Diagnosis and Pathogenetic Mechanisms of Rare Genetic Diseases, Azienda Ospedaliero Universitaria Senese, Siena, Italy
| |
Collapse
|
7
|
Bolaños P, Calderón JC. Excitation-contraction coupling in mammalian skeletal muscle: Blending old and last-decade research. Front Physiol 2022; 13:989796. [PMID: 36117698 PMCID: PMC9478590 DOI: 10.3389/fphys.2022.989796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
The excitation–contraction coupling (ECC) in skeletal muscle refers to the Ca2+-mediated link between the membrane excitation and the mechanical contraction. The initiation and propagation of an action potential through the membranous system of the sarcolemma and the tubular network lead to the activation of the Ca2+-release units (CRU): tightly coupled dihydropyridine and ryanodine (RyR) receptors. The RyR gating allows a rapid, massive, and highly regulated release of Ca2+ from the sarcoplasmic reticulum (SR). The release from triadic places generates a sarcomeric gradient of Ca2+ concentrations ([Ca2+]) depending on the distance of a subcellular region from the CRU. Upon release, the diffusing Ca2+ has multiple fates: binds to troponin C thus activating the contractile machinery, binds to classical sarcoplasmic Ca2+ buffers such as parvalbumin, adenosine triphosphate and, experimentally, fluorescent dyes, enters the mitochondria and the SR, or is recycled through the Na+/Ca2+ exchanger and store-operated Ca2+ entry (SOCE) mechanisms. To commemorate the 7th decade after being coined, we comprehensively and critically reviewed “old”, historical landmarks and well-established concepts, and blended them with recent advances to have a complete, quantitative-focused landscape of the ECC. We discuss the: 1) elucidation of the CRU structures at near-atomic resolution and its implications for functional coupling; 2) reliable quantification of peak sarcoplasmic [Ca2+] using fast, low affinity Ca2+ dyes and the relative contributions of the Ca2+-binding mechanisms to the whole concert of Ca2+ fluxes inside the fibre; 3) articulation of this novel quantitative information with the unveiled structural details of the molecular machinery involved in mitochondrial Ca2+ handing to understand how and how much Ca2+ enters the mitochondria; 4) presence of the SOCE machinery and its different modes of activation, which awaits understanding of its magnitude and relevance in situ; 5) pharmacology of the ECC, and 6) emerging topics such as the use and potential applications of super-resolution and induced pluripotent stem cells (iPSC) in ECC. Blending the old with the new works better!
Collapse
Affiliation(s)
- Pura Bolaños
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Juan C. Calderón
- Physiology and Biochemistry Research Group-PHYSIS, Faculty of Medicine, University of Antioquia, Medellín, Colombia
- *Correspondence: Juan C. Calderón,
| |
Collapse
|
8
|
Rossi D, Pierantozzi E, Amadsun DO, Buonocore S, Rubino EM, Sorrentino V. The Sarcoplasmic Reticulum of Skeletal Muscle Cells: A Labyrinth of Membrane Contact Sites. Biomolecules 2022; 12:488. [PMID: 35454077 PMCID: PMC9026860 DOI: 10.3390/biom12040488] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 03/14/2022] [Accepted: 03/18/2022] [Indexed: 12/17/2022] Open
Abstract
The sarcoplasmic reticulum of skeletal muscle cells is a highly ordered structure consisting of an intricate network of tubules and cisternae specialized for regulating Ca2+ homeostasis in the context of muscle contraction. The sarcoplasmic reticulum contains several proteins, some of which support Ca2+ storage and release, while others regulate the formation and maintenance of this highly convoluted organelle and mediate the interaction with other components of the muscle fiber. In this review, some of the main issues concerning the biology of the sarcoplasmic reticulum will be described and discussed; particular attention will be addressed to the structure and function of the two domains of the sarcoplasmic reticulum supporting the excitation-contraction coupling and Ca2+-uptake mechanisms.
Collapse
Affiliation(s)
- Daniela Rossi
- Department of Molecular and Developmental Medicine, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; (E.P.); (D.O.A.); (S.B.); (E.M.R.); (V.S.)
| | | | | | | | | | | |
Collapse
|
9
|
Quantification of the calcium signaling deficit in muscles devoid of triadin. PLoS One 2022; 17:e0264146. [PMID: 35213584 PMCID: PMC8880904 DOI: 10.1371/journal.pone.0264146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 02/03/2022] [Indexed: 11/24/2022] Open
Abstract
Triadin, a protein of the sarcoplasmic reticulum (SR) of striated muscles, anchors the calcium-storing protein calsequestrin to calcium release RyR channels at the junction with t-tubules, and modulates these channels by conformational effects. Triadin ablation induces structural SR changes and alters the expression of other proteins. Here we quantify alterations of calcium signaling in single skeletal myofibers of constitutive triadin-null mice. We find higher resting cytosolic and lower SR-luminal [Ca2+], 40% lower calsequestrin expression, and more CaV1.1, RyR1 and SERCA1. Despite the increased CaV1.1, the mobile intramembrane charge was reduced by ~20% in Triadin-null fibers. The initial peak of calcium release flux by pulse depolarization was minimally altered in the null fibers (revealing an increase in peak calcium permeability). The “hump” phase that followed, attributable to calcium detaching from calsequestrin, was 25% lower, a smaller change than expected from the reduced calsequestrin content and calcium saturation. The exponential decay rate of calcium transients was 25% higher, consistent with the higher SERCA1 content. Recovery of calcium flux after a depleting depolarization was faster in triadin-null myofibers, consistent with the increased uptake rate and lower SR calsequestrin content. In sum, the triadin knockout determines an increased RyR1 channel openness, which depletes the SR, a substantial loss of calsequestrin and gains in other couplon proteins. Powerful functional compensations ensue: activation of SOCE that increases [Ca2+]cyto; increased SERCA1 activity, which limits the decrease in [Ca2+]SR and a restoration of SR calcium storage of unknown substrate. Together, they effectively limit the functional loss in skeletal muscles.
Collapse
|
10
|
Rossi D, Lorenzini S, Pierantozzi E, Van Petegem F, Amadsun DO, Sorrentino V. Multiple regions of junctin drive interaction with calsequestrin-1 and localization at triads in skeletal muscle. J Cell Sci 2021; 135:274105. [PMID: 34913055 DOI: 10.1242/jcs.259185] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 12/08/2021] [Indexed: 11/20/2022] Open
Abstract
Junctin is a transmembrane protein of striated muscles, localized at the junctional sarcoplasmic reticulum (j-SR). It is characterized by a luminal C-terminal tail, through which it functionally interacts with calsequestrin and the ryanodine receptor. Interaction with calsequestrin was ascribed to the presence of stretches of charged amino acids. However, the regions able to bind calsequestrin have not been defined in detail. We report here that, in non-muscle cells, junctin and calsequestrin assemble in long linear regions within the endoplasmic reticulum, mirroring the formation of calsequestrin polymers. In differentiating myotubes, the two proteins co-localize at triads, where they assemble with other j-SR proteins. By performing GST pull-down assays with distinct regions of the junctin tail, we identified two KEKE motifs able to bind calsequestrin. In addition, stretches of charged amino acids downstream these motifs were found to be also able to bind calsequestrin and the ryanodine receptor. Deletion of even one of these regions impaired the ability of junctin to localize at the j-SR, suggesting that interaction with other proteins at this site represents a key element in junctin targeting.
Collapse
Affiliation(s)
- Daniela Rossi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Stefania Lorenzini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Enrico Pierantozzi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
| | | | - Vincenzo Sorrentino
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| |
Collapse
|
11
|
Lilliu E, Koenig S, Koenig X, Frieden M. Store-Operated Calcium Entry in Skeletal Muscle: What Makes It Different? Cells 2021; 10:cells10092356. [PMID: 34572005 PMCID: PMC8468011 DOI: 10.3390/cells10092356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/03/2021] [Accepted: 09/04/2021] [Indexed: 01/26/2023] Open
Abstract
Current knowledge on store-operated Ca2+ entry (SOCE) regarding its localization, kinetics, and regulation is mostly derived from studies performed in non-excitable cells. After a long time of relative disinterest in skeletal muscle SOCE, this mechanism is now recognized as an essential contributor to muscle physiology, as highlighted by the muscle pathologies that are associated with mutations in the SOCE molecules STIM1 and Orai1. This review mainly focuses on the peculiar aspects of skeletal muscle SOCE that differentiate it from its counterpart found in non-excitable cells. This includes questions about SOCE localization and the movement of respective proteins in the highly organized skeletal muscle fibers, as well as the diversity of expressed STIM isoforms and their differential expression between muscle fiber types. The emerging evidence of a phasic SOCE, which is activated during EC coupling, and its physiological implication is described as well. The specific issues related to the use of SOCE modulators in skeletal muscles are discussed. This review highlights the complexity of SOCE activation and its regulation in skeletal muscle, with an emphasis on the most recent findings and the aim to reach a current picture of this mesmerizing phenomenon.
Collapse
Affiliation(s)
- Elena Lilliu
- Center for Physiology and Pharmacology, Department of Neurophysiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria;
| | - Stéphane Koenig
- Department of Cell Physiology and Metabolism, University of Geneva, 1201 Geneva, Switzerland;
| | - Xaver Koenig
- Center for Physiology and Pharmacology, Department of Neurophysiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria;
- Correspondence: (X.K.); (M.F.)
| | - Maud Frieden
- Department of Cell Physiology and Metabolism, University of Geneva, 1201 Geneva, Switzerland;
- Correspondence: (X.K.); (M.F.)
| |
Collapse
|
12
|
Protasi F, Pietrangelo L, Boncompagni S. Improper Remodeling of Organelles Deputed to Ca 2+ Handling and Aerobic ATP Production Underlies Muscle Dysfunction in Ageing. Int J Mol Sci 2021; 22:6195. [PMID: 34201319 PMCID: PMC8228829 DOI: 10.3390/ijms22126195] [Citation(s) in RCA: 11] [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: 04/30/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 12/28/2022] Open
Abstract
Proper skeletal muscle function is controlled by intracellular Ca2+ concentration and by efficient production of energy (ATP), which, in turn, depend on: (a) the release and re-uptake of Ca2+ from sarcoplasmic-reticulum (SR) during excitation-contraction (EC) coupling, which controls the contraction and relaxation of sarcomeres; (b) the uptake of Ca2+ into the mitochondrial matrix, which stimulates aerobic ATP production; and finally (c) the entry of Ca2+ from the extracellular space via store-operated Ca2+ entry (SOCE), a mechanism that is important to limit/delay muscle fatigue. Abnormalities in Ca2+ handling underlie many physio-pathological conditions, including dysfunction in ageing. The specific focus of this review is to discuss the importance of the proper architecture of organelles and membrane systems involved in the mechanisms introduced above for the correct skeletal muscle function. We reviewed the existing literature about EC coupling, mitochondrial Ca2+ uptake, SOCE and about the structural membranes and organelles deputed to those functions and finally, we summarized the data collected in different, but complementary, projects studying changes caused by denervation and ageing to the structure and positioning of those organelles: a. denervation of muscle fibers-an event that contributes, to some degree, to muscle loss in ageing (known as sarcopenia)-causes misplacement and damage: (i) of membrane structures involved in EC coupling (calcium release units, CRUs) and (ii) of the mitochondrial network; b. sedentary ageing causes partial disarray/damage of CRUs and of calcium entry units (CEUs, structures involved in SOCE) and loss/misplacement of mitochondria; c. functional electrical stimulation (FES) and regular exercise promote the rescue/maintenance of the proper architecture of CRUs, CEUs, and of mitochondria in both denervation and ageing. All these structural changes were accompanied by related functional changes, i.e., loss/decay in function caused by denervation and ageing, and improved function following FES or exercise. These data suggest that the integrity and proper disposition of intracellular organelles deputed to Ca2+ handling and aerobic generation of ATP is challenged by inactivity (or reduced activity); modifications in the architecture of these intracellular membrane systems may contribute to muscle dysfunction in ageing and sarcopenia.
Collapse
Affiliation(s)
- Feliciano Protasi
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, I-66100 Chieti, Italy; (L.P.); (S.B.)
- DMSI, Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, I-66100 Chieti, Italy
| | - Laura Pietrangelo
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, I-66100 Chieti, Italy; (L.P.); (S.B.)
- DMSI, Department of Medicine and Aging Sciences, University G. d’Annunzio of Chieti-Pescara, I-66100 Chieti, Italy
| | - Simona Boncompagni
- CAST, Center for Advanced Studies and Technology, University G. d’Annunzio of Chieti-Pescara, I-66100 Chieti, Italy; (L.P.); (S.B.)
- DNICS, Department of Neuroscience and Clinical Sciences, University G. d’Annunzio of Chieti-Pescara, I-66100 Chieti, Italy
| |
Collapse
|
13
|
Palahniuk C, Mutawe M, Gilchrist JSC. Luminal Ca 2+ regulation of RyR1 Ca 2+ channel leak activation and inactivation in sarcoplasmic reticulum membrane vesicles. Can J Physiol Pharmacol 2021; 99:192-206. [PMID: 33161753 DOI: 10.1139/cjpp-2020-0409] [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] [Indexed: 11/22/2022]
Abstract
In this study, we tested the hypothesis that the RyR1 Ca2+ channel closure is sensitive to outward trans-SR membrane Ca2+ gradients established by SERCA1 pumping. To perform these studies, we employed stopped-flow rapid-kinetic fluorescence methods to measure and assess how variation in trans-SR membrane Ca2+ distribution affects evolution of RyR1 Ca2+ leaks in RyR1/ CASQ1/SERCA1-rich membrane vesicles. Our studies showed that rapid filling of a Mag-Fura-2-sensitive free Ca2+ pool during SERCA1-mediated Ca2+ sequestration appears to be a crucial condition allowing RyR1 Ca2+ channels to close once reloading of luminal Ca2+ stores is complete. Disruption in the filling of this pool caused activation of Ruthenium Red inhibitable RyR1 Ca2+ leaks, suggesting that SERCA1 pump formation of outward Ca2+ gradients is an important aspect of Ca2+ flux control channel opening and closing. In addition, our observed ryanodine-induced shift in luminal Ca2+ from free to a CTC-Ca+-sensitive, CASQ1-associated bound compartment underscores the complex organization and regulation of SR luminal Ca2+. Our study provides strong evidence that RyR1 functional states directly and indirectly influence the compartmentation of luminal Ca2+. This, in turn, is influenced by the activity of SERCA1 pumps to fill luminal pools while synchronously reducing Ca2+ levels on the cytosolic face of RyR1 channels.
Collapse
Affiliation(s)
- C Palahniuk
- Department of Biology, St. Catherine University, 2004 Randolph Ave., St. Paul, MN 55105, USA
| | - M Mutawe
- Genome Analysis Core (GAC), 13-66 Stabile Building, MAYO Clinic, Rochester, MN 55905, USA
| | - J S C Gilchrist
- Department of Oral Biology, Rady Faculty of Health Sciences, University of Manitoba, MB R3E 0W2, Canada
| |
Collapse
|
14
|
Transcriptome Profiling across Five Tissues of Giant Panda. BIOMED RESEARCH INTERNATIONAL 2020; 2020:3852586. [PMID: 32851066 PMCID: PMC7436357 DOI: 10.1155/2020/3852586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 05/03/2020] [Accepted: 06/01/2020] [Indexed: 11/18/2022]
Abstract
Gene differential expression studies can serve to explore and understand the laws and characteristics of animal life activities, and the difference in gene expression between different animal tissues has been well demonstrated and studied. However, for the world-famous rare and protected species giant panda (Ailuropoda melanoleuca), only the transcriptome of the blood and spleen has been reported separately. Here, in order to explore the transcriptome differences between the different tissues of the giant panda, transcriptome profiles of the heart, liver, spleen, lung, and kidney from five captive giant pandas were constructed with Illumina HiSeq 2500 platform. The comparative analysis of the intertissue gene expression patterns was carried out based on the generated RNA sequencing datasets. Analyses of Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and protein-protein interaction (PPI) network were performed according to the identified differentially expressed genes (DEGs). We generated 194.52 GB clean base data from twenty-five sequencing libraries and identified 18,701 genes, including 3492 novel genes. With corrected p value <0.05 and |log2FoldChange| >2, we finally obtained 921, 553, 574, 457, and 638 tissue-specific DEGs in the heart, liver, spleen, lung, and kidney, respectively. In addition, we identified TTN, CAV3, LDB3, TRDN, and ACTN2 in the heart; FGA, AHSG, and SERPINC1 in the liver; CD19, CD79B, and IL21R in the spleen; NKX2-4 and SFTPB in the lung; GC and HRG in the kidney as hub genes in the PPI network. The results of the analyses showed a similar gene expression pattern between the spleen and lung. This study provided for the first time the heart, liver, lung, and kidney's transcriptome resources of the giant panda, and it provided a valuable resource for further genetic research or other potential research.
Collapse
|
15
|
Protasi F, Pietrangelo L, Boncompagni S. Calcium entry units (CEUs): perspectives in skeletal muscle function and disease. J Muscle Res Cell Motil 2020; 42:233-249. [PMID: 32812118 PMCID: PMC8332569 DOI: 10.1007/s10974-020-09586-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 08/03/2020] [Indexed: 12/28/2022]
Abstract
In the last decades the term Store-operated Ca2+ entry (SOCE) has been used in the scientific literature to describe an ubiquitous cellular mechanism that allows recovery of calcium (Ca2+) from the extracellular space. SOCE is triggered by a reduction of Ca2+ content (i.e. depletion) in intracellular stores, i.e. endoplasmic or sarcoplasmic reticulum (ER and SR). In skeletal muscle the mechanism is primarily mediated by a physical interaction between stromal interaction molecule-1 (STIM1), a Ca2+ sensor located in the SR membrane, and ORAI1, a Ca2+-permeable channel of external membranes, located in transverse tubules (TTs), the invaginations of the plasma membrane (PM) deputed to propagation of action potentials. It is generally accepted that in skeletal muscle SOCE is important to limit muscle fatigue during repetitive stimulation. We recently discovered that exercise promotes the assembly of new intracellular junctions that contains colocalized STIM1 and ORAI1, and that the presence of these new junctions increases Ca2+ entry via ORAI1, while improving fatigue resistance during repetitive stimulation. Based on these findings we named these new junctions Ca2+ Entry Units (CEUs). CEUs are dynamic organelles that assemble during muscle activity and disassemble during recovery thanks to the plasticity of the SR (containing STIM1) and the elongation/retraction of TTs (bearing ORAI1). Interestingly, similar structures described as SR stacks were previously reported in different mouse models carrying mutations in proteins involved in Ca2+ handling (calsequestrin-null mice; triadin and junctin null mice, etc.) or associated to microtubules (MAP6 knockout mice). Mutations in Stim1 and Orai1 (and calsequestrin-1) genes have been associated to tubular aggregate myopathy (TAM), a muscular disease characterized by: (a) muscle pain, cramping, or weakness that begins in childhood and worsens over time, and (b) the presence of large accumulations of ordered SR tubes (tubular aggregates, TAs) that do not contain myofibrils, mitochondria, nor TTs. Interestingly, TAs are also present in fast twitch muscle fibers of ageing mice. Several important issues remain un-answered: (a) the molecular mechanisms and signals that trigger the remodeling of membranes and the functional activation of SOCE during exercise are unclear; and (b) how dysfunctional SOCE and/or mutations in Stim1, Orai1 and calsequestrin (Casq1) genes lead to the formation of tubular aggregates (TAs) in aging and disease deserve investigation.
Collapse
Affiliation(s)
- Feliciano Protasi
- CAST, Center for Advanced Studies and Technology, University G. d'Annunzio of Chieti-Pescara, 66100, Chieti, Italy.
- DMSI, Department of Medicine and Aging Sciences, University G. d'Annunzio of Chieti-Pescara, 66100, Chieti, Italy.
| | - Laura Pietrangelo
- CAST, Center for Advanced Studies and Technology, University G. d'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
- DMSI, Department of Medicine and Aging Sciences, University G. d'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
| | - Simona Boncompagni
- CAST, Center for Advanced Studies and Technology, University G. d'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
- DNICS, Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
| |
Collapse
|
16
|
Wang Q, Michalak M. Calsequestrin. Structure, function, and evolution. Cell Calcium 2020; 90:102242. [PMID: 32574906 DOI: 10.1016/j.ceca.2020.102242] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/05/2020] [Accepted: 06/06/2020] [Indexed: 12/25/2022]
Abstract
Calsequestrin is the major Ca2+ binding protein in the sarcoplasmic reticulum (SR), serves as the main Ca2+ storage and buffering protein and is an important regulator of Ca2+ release channels in both skeletal and cardiac muscle. It is anchored at the junctional SR membrane through interactions with membrane proteins and undergoes reversible polymerization with increasing Ca2+ concentration. Calsequestrin provides high local Ca2+ at the junctional SR and communicates changes in luminal Ca2+ concentration to Ca2+ release channels, thus it is an essential component of excitation-contraction coupling. Recent studies reveal new insights on calsequestrin trafficking, Ca2+ binding, protein evolution, protein-protein interactions, stress responses and the molecular basis of related human muscle disease, including catecholaminergic polymorphic ventricular tachycardia (CPVT). Here we provide a comprehensive overview of calsequestrin, with recent advances in structure, diverse functions, phylogenetic analysis, and its role in muscle physiology, stress responses and human pathology.
Collapse
Affiliation(s)
- Qian Wang
- Department of Biochemistry, University of Alberta, Edmonton, AB, T6H 2S7, Canada
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB, T6H 2S7, Canada.
| |
Collapse
|
17
|
Rossi D, Gamberucci A, Pierantozzi E, Amato C, Migliore L, Sorrentino V. Calsequestrin, a key protein in striated muscle health and disease. J Muscle Res Cell Motil 2020; 42:267-279. [PMID: 32488451 DOI: 10.1007/s10974-020-09583-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 05/22/2020] [Accepted: 05/26/2020] [Indexed: 10/24/2022]
Abstract
Calsequestrin (CASQ) is the most abundant Ca2+ binding protein localized in the sarcoplasmic reticulum (SR) of skeletal and cardiac muscle. The genome of vertebrates contains two genes, CASQ1 and CASQ2. CASQ1 and CASQ2 have a high level of homology, but show specific patterns of expression. Fast-twitch skeletal muscle fibers express only CASQ1, both CASQ1 and CASQ2 are present in slow-twitch skeletal muscle fibers, while CASQ2 is the only protein present in cardiomyocytes. Depending on the intraluminal SR Ca2+ levels, CASQ monomers assemble to form large polymers, which increase their Ca2+ binding ability. CASQ interacts with triadin and junctin, two additional SR proteins which contribute to localize CASQ to the junctional region of the SR (j-SR) and also modulate CASQ ability to polymerize into large macromolecular complexes. In addition to its ability to bind Ca2+ in the SR, CASQ appears also to be able to contribute to regulation of Ca2+ homeostasis in muscle cells. Both CASQ1 and CASQ2 are able to either activate and inhibit the ryanodine receptors (RyRs) calcium release channels, likely through their interactions with junctin and triadin. Additional evidence indicates that CASQ1 contributes to regulate the mechanism of store operated calcium entry in skeletal muscle via a direct interaction with the Stromal Interaction Molecule 1 (STIM1). Mutations in CASQ2 and CASQ1 have been identified, respectively, in patients with catecholamine-induced polymorphic ventricular tachycardia and in patients with some forms of myopathy. This review will highlight recent developments in understanding CASQ1 and CASQ2 in health and diseases.
Collapse
Affiliation(s)
- Daniela Rossi
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Via A. Moro, 2, 53100, Siena, Italy.
| | - Alessandra Gamberucci
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Via A. Moro, 2, 53100, Siena, Italy
| | - Enrico Pierantozzi
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Via A. Moro, 2, 53100, Siena, Italy
| | - Caterina Amato
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Via A. Moro, 2, 53100, Siena, Italy
| | - Loredana Migliore
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Via A. Moro, 2, 53100, Siena, Italy
| | - Vincenzo Sorrentino
- Molecular Medicine Section, Department of Molecular and Developmental Medicine, University of Siena, Via A. Moro, 2, 53100, Siena, Italy
| |
Collapse
|
18
|
Michelucci A, Boncompagni S, Pietrangelo L, García-Castañeda M, Takano T, Malik S, Dirksen RT, Protasi F. Transverse tubule remodeling enhances Orai1-dependent Ca 2+ entry in skeletal muscle. eLife 2019; 8:47576. [PMID: 31657717 PMCID: PMC6837846 DOI: 10.7554/elife.47576] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 10/24/2019] [Indexed: 12/18/2022] Open
Abstract
Exercise promotes the formation of intracellular junctions in skeletal muscle between stacks of sarcoplasmic reticulum (SR) cisternae and extensions of transverse-tubules (TT) that increase co-localization of proteins required for store-operated Ca2+ entry (SOCE). Here, we report that SOCE, peak Ca2+ transient amplitude and muscle force production during repetitive stimulation are increased after exercise in parallel with the time course of TT association with SR-stacks. Unexpectedly, exercise also activated constitutive Ca2+ entry coincident with a modest decrease in total releasable Ca2+ store content. Importantly, this decrease in releasable Ca2+ store content observed after exercise was reversed by repetitive high-frequency stimulation, consistent with enhanced SOCE. The functional benefits of exercise on SOCE, constitutive Ca2+ entry and muscle force production were lost in mice with muscle-specific loss of Orai1 function. These results indicate that TT association with SR-stacks enhances Orai1-dependent SOCE to optimize Ca2+ dynamics and muscle contractile function during acute exercise.
Collapse
Affiliation(s)
- Antonio Michelucci
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, United States.,Center for Research on Ageing and Translational Medicine (CeSI-MeT), University Gabriele d'Annunzio, Chieti, Italy
| | - Simona Boncompagni
- Center for Research on Ageing and Translational Medicine (CeSI-MeT), University Gabriele d'Annunzio, Chieti, Italy.,Department of Neuroscience, Imaging and Clinical Sciences (DNICS), University Gabriele d'Annunzio, Chieti, Italy
| | - Laura Pietrangelo
- Center for Research on Ageing and Translational Medicine (CeSI-MeT), University Gabriele d'Annunzio, Chieti, Italy.,Department of Neuroscience, Imaging and Clinical Sciences (DNICS), University Gabriele d'Annunzio, Chieti, Italy
| | - Maricela García-Castañeda
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, United States
| | - Takahiro Takano
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, United States
| | - Sundeep Malik
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, United States
| | - Robert T Dirksen
- Department of Pharmacology and Physiology, University of Rochester School of Medicine and Dentistry, Rochester, United States
| | - Feliciano Protasi
- Center for Research on Ageing and Translational Medicine (CeSI-MeT), University Gabriele d'Annunzio, Chieti, Italy.,Department of Medicine and Ageing Sciences (DMSI), University Gabriele d'Annunzio, Chieti, Italy
| |
Collapse
|
19
|
Rossi D, Gigli L, Gamberucci A, Bordoni R, Pietrelli A, Lorenzini S, Pierantozzi E, Peretto G, De Bellis G, Della Bella P, Ferrari M, Sorrentino V, Benedetti S, Sala S, Di Resta C. A novel homozygous mutation in the TRDN gene causes a severe form of pediatric malignant ventricular arrhythmia. Heart Rhythm 2019; 17:296-304. [PMID: 31437535 DOI: 10.1016/j.hrthm.2019.08.018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Indexed: 12/26/2022]
Abstract
BACKGROUND Triadin is a protein expressed in cardiac and skeletal muscle that has an essential role in the structure and functional regulation of calcium release units and excitation-contraction coupling. Mutations in the triadin gene (TRDN) have been described in different forms of human arrhythmia syndromes with early onset and severe arrhythmogenic phenotype, including triadin knockout syndrome. OBJECTIVE The purpose of this study was to characterize the pathogenetic mechanism underlying a case of severe pediatric malignant arrhythmia associated with a defect in the TRDN gene. METHODS We used a trio whole exome sequencing approach to identify the genetic defect in a 2-year-old boy who had been resuscitated from sudden cardiac arrest and had frequent episodes of ventricular fibrillation and a family history positive for sudden death. We then performed in vitro functional analysis to investigate possible pathogenic mechanisms underlying this severe phenotype. RESULTS We identified a novel homozygous missense variant (p.L56P) in the TRDN gene in the proband that was inherited from the heterozygous unaffected parents. Expression of a green fluorescent protein (GFP)-tagged mutant human cardiac triadin isoform (TRISK32-L56P-GFP) in heterologous systems revealed that the mutation alters protein dynamics. Furthermore, when co-expressed with the type 2 ryanodine receptor, caffeine-induced calcium release from TRISK32-L56P-GFP was relatively lower compared to that observed with the wild-type construct. CONCLUSION The results of this study allowed us to hypothesize a pathogenic mechanism underlying this rare arrhythmogenic recessive form, suggesting that the mutant protein potentially can trigger arrhythmias by altering calcium homeostasis.
Collapse
Affiliation(s)
- Daniela Rossi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Lorenzo Gigli
- Department of Arrhythmology, IRCCS San Raffaele Hospital, Milan, Italy
| | - Alessandra Gamberucci
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Roberta Bordoni
- Institute of Biomedical Technologies, National Research Council of Italy, Milan, Italy
| | - Alessandro Pietrelli
- Institute of Biomedical Technologies, National Research Council of Italy, Milan, Italy
| | - Stefania Lorenzini
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Enrico Pierantozzi
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Giovanni Peretto
- Department of Arrhythmology, IRCCS San Raffaele Hospital, Milan, Italy
| | - Gianluca De Bellis
- Institute of Biomedical Technologies, National Research Council of Italy, Milan, Italy
| | - Paolo Della Bella
- Department of Arrhythmology, IRCCS San Raffaele Hospital, Milan, Italy
| | - Maurizio Ferrari
- Vita-Salute San Raffaele University, Milan, Italy; Laboratory of Clinical Molecular Biology and Cytogenetics, IRCCS San Raffaele Hospital, Milan, Italy; Genomic Unit for the Diagnosis of Human Pathologies, Division of Genetics and Cellular Biology, IRCCS San Raffaele Hospital, Milan, Italy
| | - Vincenzo Sorrentino
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Sara Benedetti
- Laboratory of Clinical Molecular Biology and Cytogenetics, IRCCS San Raffaele Hospital, Milan, Italy
| | - Simone Sala
- Department of Arrhythmology, IRCCS San Raffaele Hospital, Milan, Italy
| | - Chiara Di Resta
- Vita-Salute San Raffaele University, Milan, Italy; Genomic Unit for the Diagnosis of Human Pathologies, Division of Genetics and Cellular Biology, IRCCS San Raffaele Hospital, Milan, Italy.
| |
Collapse
|
20
|
Sébastien M, Giannesini B, Aubin P, Brocard J, Chivet M, Pietrangelo L, Boncompagni S, Bosc C, Brocard J, Rendu J, Gory-Fauré S, Andrieux A, Fourest-Lieuvin A, Fauré J, Marty I. Deletion of the microtubule-associated protein 6 (MAP6) results in skeletal muscle dysfunction. Skelet Muscle 2018; 8:30. [PMID: 30231928 PMCID: PMC6147105 DOI: 10.1186/s13395-018-0176-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/12/2018] [Indexed: 01/23/2023] Open
Abstract
Background The skeletal muscle fiber has a specific and precise intracellular organization which is at the basis of an efficient muscle contraction. Microtubules are long known to play a major role in the function and organization of many cells, but in skeletal muscle, the contribution of the microtubule cytoskeleton to the efficiency of contraction has only recently been studied. The microtubule network is dynamic and is regulated by many microtubule-associated proteins (MAPs). In the present study, the role of the MAP6 protein in skeletal muscle organization and function has been studied using the MAP6 knockout mouse line. Methods The presence of MAP6 transcripts and proteins was shown in mouse muscle homogenates and primary culture using RT-PCR and western blot. The in vivo evaluation of muscle force of MAP6 knockout (KO) mice was performed on anesthetized animals using electrostimulation coupled to mechanical measurement and multimodal magnetic resonance. The impact of MAP6 deletion on microtubule organization and intracellular structures was studied using immunofluorescent labeling and electron microscopy, and on calcium release for muscle contraction using Fluo-4 calcium imaging on cultured myotubes. Statistical analysis was performed using Student’s t test or the Mann-Whitney test. Results We demonstrate the presence of MAP6 transcripts and proteins in skeletal muscle. Deletion of MAP6 results in a large number of muscle modifications: muscle weakness associated with slight muscle atrophy, alterations of microtubule network and sarcoplasmic reticulum organization, and reduction in calcium release. Conclusion Altogether, our results demonstrate that MAP6 is involved in skeletal muscle function. Its deletion results in alterations in skeletal muscle contraction which contribute to the global deleterious phenotype of the MAP6 KO mice. As MAP6 KO mouse line is a model for schizophrenia, our work points to a possible muscle weakness associated to some forms of schizophrenia. Electronic supplementary material The online version of this article (10.1186/s13395-018-0176-8) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Muriel Sébastien
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | | | - Perrine Aubin
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Julie Brocard
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Mathilde Chivet
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Laura Pietrangelo
- CeSI-Met & DNICS, University G. d' Annunzio of Chieti, I-66100, Chieti, Italy
| | - Simona Boncompagni
- CeSI-Met & DNICS, University G. d' Annunzio of Chieti, I-66100, Chieti, Italy
| | - Christophe Bosc
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Jacques Brocard
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - John Rendu
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CHU Grenoble, Biochimie et Génétique Moléculaire, F-38000, Grenoble, France
| | - Sylvie Gory-Fauré
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France
| | - Annie Andrieux
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CEA-Grenoble, BIG, F-38000, Grenoble, France
| | - Anne Fourest-Lieuvin
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CEA-Grenoble, BIG, F-38000, Grenoble, France
| | - Julien Fauré
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France.,University Grenoble Alpes, F-38000, Grenoble, France.,CHU Grenoble, Biochimie et Génétique Moléculaire, F-38000, Grenoble, France
| | - Isabelle Marty
- INSERM 1216, Grenoble Institute of Neurosciences, F-38000, Grenoble, France. .,University Grenoble Alpes, F-38000, Grenoble, France. .,GIN- Inserm U1216 - Bat EJ Safra, Chemin Fortuné Ferrini, 38700, La Tronche, France.
| |
Collapse
|
21
|
Carraro U. Exciting perspectives for Translational Myology in the Abstracts of the 2018Spring PaduaMuscleDays: Giovanni Salviati Memorial - Chapter III - Abstracts of March 16, 2018. Eur J Transl Myol 2018; 28:7365. [PMID: 30057727 PMCID: PMC6047881 DOI: 10.4081/ejtm.2018.7365] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 02/20/2018] [Indexed: 11/23/2022] Open
Abstract
Myologists working in Padua (Italy) were able to continue a half-century tradition of studies of skeletal muscles, that started with a research on fever, specifically if and how skeletal muscle contribute to it by burning bacterial toxin. Beside main publications in high-impact-factor journals by Padua myologists, I hope to convince readers (and myself) of the relevance of the editing Basic and Applied Myology (BAM), retitled from 2010 European Journal of Translational Myology (EJTM), of the institution of the Interdepartmental Research Center of Myology of the University of Padova (CIR-Myo), and of a long series of International Conferences organized in Euganei Hills and Padova, that is, the PaduaMuscleDays. The 2018Spring PaduaMuscleDays (2018SpPMD), were held in Euganei Hills and Padua (Italy), in March 14-17, and were dedicated to Giovanni Salviati. The main event of the “Giovanni Salviati Memorial”, was held in the Aula Guariento, Accademia Galileiana di Scienze, Lettere ed Arti of Padua to honor a beloved friend and excellent scientist 20 years after his premature passing. Using the words of Prof. Nicola Rizzuto, we all share his believe that Giovanni “will be remembered not only for his talent and originality as a biochemist, but also for his unassuming and humanistic personality, a rare quality in highly successful people like Giovanni. The best way to remember such a person is to gather pupils and colleagues, who shared with him the same scientific interests and ask them to discuss recent advances in their own fields, just as Giovanni have liked to do”. Since Giovanni’s friends sent many abstracts still influenced by their previous collaboration with him, all the Sessions of the 2018SpPMD reflect both to the research aims of Giovanni Salviati and the traditional topics of the PaduaMuscleDays, that is, basics and applications of physical, molecular and cellular strategies to maintain or recover functions of skeletal muscles. The translational researches summarized in the 2018SpPMD Abstracts are at the appropriate high level to attract approval of Ethical Committees, the interest of International Granting Agencies and approval for publication in top quality, international journals. The abstracts of the March 16, 2018 Padua Muscle Day are listed in this chapter III. All 2018SpPMD Abstracts are indexed at the end of the Chapter IV.
Collapse
Affiliation(s)
- Ugo Carraro
- Laboratory of Translational Myology, Department of Biomedical Sciences, University of Padova.,A&C M-C Foundation for Translational Myology, Padova.,IRCCS Fondazione Ospedale San Camillo, Venezia-Lido, Italy
| |
Collapse
|
22
|
Franzini-Armstrong C. The relationship between form and function throughout the history of excitation-contraction coupling. J Gen Physiol 2018; 150:189-210. [PMID: 29317466 PMCID: PMC5806676 DOI: 10.1085/jgp.201711889] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Franzini-Armstrong reviews the development of the excitation–contraction coupling field over time. The concept of excitation–contraction coupling is almost as old as Journal of General Physiology. It was understood as early as the 1940s that a series of stereotyped events is responsible for the rapid contraction response of muscle fibers to an initial electrical event at the surface. These early developments, now lost in what seems to be the far past for most young investigators, have provided an endless source of experimental approaches. In this Milestone in Physiology, I describe in detail the experiments and concepts that introduced and established the field of excitation–contraction coupling in skeletal muscle. More recent advances are presented in an abbreviated form, as readers are likely to be familiar with recent work in the field.
Collapse
Affiliation(s)
- Clara Franzini-Armstrong
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA
| |
Collapse
|
23
|
Boncompagni S, Michelucci A, Pietrangelo L, Dirksen RT, Protasi F. Exercise-dependent formation of new junctions that promote STIM1-Orai1 assembly in skeletal muscle. Sci Rep 2017; 7:14286. [PMID: 29079778 PMCID: PMC5660245 DOI: 10.1038/s41598-017-14134-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 10/09/2017] [Indexed: 12/14/2022] Open
Abstract
Store-operated Ca2+ entry (SOCE), a ubiquitous mechanism that allows recovery of Ca2+ ions from the extracellular space, has been proposed to limit fatigue during repetitive skeletal muscle activity. However, the subcellular location for SOCE in muscle fibers has not been unequivocally identified. Here we show that exercise drives a significant remodeling of the sarcotubular system to form previously unidentified junctions between the sarcoplasmic reticulum (SR) and transverse-tubules (TTs). We also demonstrate that these new SR-TT junctions contain the molecular machinery that mediate SOCE: stromal interaction molecule-1 (STIM1), which functions as the SR Ca2+ sensor, and Orai1, the Ca2+-permeable channel in the TT. In addition, EDL muscles isolated from exercised mice exhibit an increased capability of maintaining contractile force during repetitive stimulation in the presence of 2.5 mM extracellular Ca2+, compared to muscles from control mice. This functional difference is significantly reduced by either replacement of extracellular Ca2+ with Mg2+ or the addition of SOCE inhibitors (BTP-2 and 2-APB). We propose that the new SR-TT junctions formed during exercise, and that contain STIM1 and Orai1, function as Ca2+Entry Units (CEUs), structures that provide a pathway to rapidly recover Ca2+ ions from the extracellular space during repetitive muscle activity.
Collapse
Affiliation(s)
- Simona Boncompagni
- CeSI-Met - Center for Research on Ageing and Translational Medicine, University G. d'Annunzio, Chieti, I-66100, Italy.,DNICS - Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, Chieti, I-66100, Italy
| | - Antonio Michelucci
- CeSI-Met - Center for Research on Ageing and Translational Medicine, University G. d'Annunzio, Chieti, I-66100, Italy.,DNICS - Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, Chieti, I-66100, Italy
| | - Laura Pietrangelo
- CeSI-Met - Center for Research on Ageing and Translational Medicine, University G. d'Annunzio, Chieti, I-66100, Italy.,DNICS - Department of Neuroscience, Imaging and Clinical Sciences, University G. d'Annunzio, Chieti, I-66100, Italy
| | - Robert T Dirksen
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Feliciano Protasi
- CeSI-Met - Center for Research on Ageing and Translational Medicine, University G. d'Annunzio, Chieti, I-66100, Italy. .,DMSI - Department of Medicine and Aging Science, University G. d'Annunzio, Chieti, I-66100, Italy.
| |
Collapse
|
24
|
Dulhunty AF, Wei-LaPierre L, Casarotto MG, Beard NA. Core skeletal muscle ryanodine receptor calcium release complex. Clin Exp Pharmacol Physiol 2017; 44:3-12. [PMID: 27696487 DOI: 10.1111/1440-1681.12676] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 09/27/2016] [Accepted: 09/27/2016] [Indexed: 12/15/2022]
Abstract
The core skeletal muscle ryanodine receptor (RyR1) calcium release complex extends through three compartments of the muscle fibre, linking the extracellular environment through the cytoplasmic junctional gap to the lumen of the internal sarcoplasmic reticulum (SR) calcium store. The protein complex is essential for skeletal excitation-contraction (EC)-coupling and skeletal muscle function. Its importance is highlighted by perinatal death if any one of the EC-coupling components are missing and by myopathies associated with mutation of any of the proteins. The proteins essential for EC-coupling include the DHPR α1S subunit in the transverse tubule membrane, the DHPR β1a subunit in the cytosol and the RyR1 ion channel in the SR membrane. The other core proteins are triadin and junctin and calsequestrin, associated mainly with SR. These SR proteins are not essential for survival but exert structural and functional influences that modify the gain of EC-coupling and maintain normal muscle function. This review summarises our current knowledge of the individual protein/protein interactions within the core complex and their overall contribution to EC-coupling. We highlight significant areas that provide a continuing challenge for the field. Additional important components of the Ca2+ release complex, such as FKBP12, calmodulin, S100A1 and Stac3 are identified and reviewed elsewhere.
Collapse
Affiliation(s)
- Angela F Dulhunty
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Lan Wei-LaPierre
- Department of Physiology and Pharmacology, University of Rochester Medical Center, Rochester, NY, USA
| | - Marco G Casarotto
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Nicole A Beard
- Health Research Institute, University of Canberra, Canberra, ACT, Australia
| |
Collapse
|
25
|
Engel AG, Redhage KR, Tester DJ, Ackerman MJ, Selcen D. Congenital myopathy associated with the triadin knockout syndrome. Neurology 2017; 88:1153-1156. [PMID: 28202702 DOI: 10.1212/wnl.0000000000003745] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 12/27/2016] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Triadin is a component of the calcium release complex of cardiac and skeletal muscle. Our objective was to analyze the skeletal muscle phenotype of the triadin knockout syndrome. METHODS We performed clinical evaluation, analyzed morphologic features by light and electron microscopy, and immunolocalized triadin in skeletal muscle. RESULTS A 6-year-old boy with lifelong muscle weakness had a triadin knockout syndrome caused by compound heterozygous null mutations in triadin. Light microscopy of a deltoid muscle specimen shows multiple small abnormal spaces in all muscle fibers. Triadin immunoreactivity is absent from type 1 fibers and barely detectable in type 2 fibers. Electron microscopy reveals focally distributed dilation and degeneration of the lateral cisterns of the sarcoplasmic reticulum and loss of the triadin anchors from the preserved lateral cisterns. CONCLUSIONS Absence of triadin in humans can result in a congenital myopathy associated with profound pathologic alterations in components of the sarcoplasmic reticulum. Why only some triadin-deficient patients develop a skeletal muscle phenotype remains an unsolved question.
Collapse
Affiliation(s)
- Andrew G Engel
- From the Departments of Neurology and Muscle Research Laboratory (A.G.E., D.S.), Cardiovascular Diseases/Division of Heart Rhythm Services (A.G.E., D.S.), Pediatric and Adolescent Medicine/Division of Pediatric Cardiology (K.R.R., D.J.T., M.J.A.), and Molecular Pharmacology & Experimental Therapeutics/Windland Smith Rice Sudden Death Genomics Laboratory (K.R.R., D.J.T., M.J.A.), Mayo College of Medicine, Rochester, MN.
| | - Keeley R Redhage
- From the Departments of Neurology and Muscle Research Laboratory (A.G.E., D.S.), Cardiovascular Diseases/Division of Heart Rhythm Services (A.G.E., D.S.), Pediatric and Adolescent Medicine/Division of Pediatric Cardiology (K.R.R., D.J.T., M.J.A.), and Molecular Pharmacology & Experimental Therapeutics/Windland Smith Rice Sudden Death Genomics Laboratory (K.R.R., D.J.T., M.J.A.), Mayo College of Medicine, Rochester, MN
| | - David J Tester
- From the Departments of Neurology and Muscle Research Laboratory (A.G.E., D.S.), Cardiovascular Diseases/Division of Heart Rhythm Services (A.G.E., D.S.), Pediatric and Adolescent Medicine/Division of Pediatric Cardiology (K.R.R., D.J.T., M.J.A.), and Molecular Pharmacology & Experimental Therapeutics/Windland Smith Rice Sudden Death Genomics Laboratory (K.R.R., D.J.T., M.J.A.), Mayo College of Medicine, Rochester, MN
| | - Michael J Ackerman
- From the Departments of Neurology and Muscle Research Laboratory (A.G.E., D.S.), Cardiovascular Diseases/Division of Heart Rhythm Services (A.G.E., D.S.), Pediatric and Adolescent Medicine/Division of Pediatric Cardiology (K.R.R., D.J.T., M.J.A.), and Molecular Pharmacology & Experimental Therapeutics/Windland Smith Rice Sudden Death Genomics Laboratory (K.R.R., D.J.T., M.J.A.), Mayo College of Medicine, Rochester, MN
| | - Duygu Selcen
- From the Departments of Neurology and Muscle Research Laboratory (A.G.E., D.S.), Cardiovascular Diseases/Division of Heart Rhythm Services (A.G.E., D.S.), Pediatric and Adolescent Medicine/Division of Pediatric Cardiology (K.R.R., D.J.T., M.J.A.), and Molecular Pharmacology & Experimental Therapeutics/Windland Smith Rice Sudden Death Genomics Laboratory (K.R.R., D.J.T., M.J.A.), Mayo College of Medicine, Rochester, MN
| |
Collapse
|
26
|
Valle G, Vergani B, Sacchetto R, Reggiani C, De Rosa E, Maccatrozzo L, Nori A, Villa A, Volpe P. Characterization of fast-twitch and slow-twitch skeletal muscles of calsequestrin 2 (CASQ2)-knock out mice: unexpected adaptive changes of fast-twitch muscles only. J Muscle Res Cell Motil 2017; 37:225-233. [PMID: 28130614 DOI: 10.1007/s10974-016-9463-3] [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: 06/27/2016] [Accepted: 12/22/2016] [Indexed: 01/02/2023]
Abstract
This study investigates the functional role of calsequestrin 2 (CASQ2) in both fast-twitch and slow-twitch skeletal muscles by using CASQ2-/- mice; CASQ2 is expressed throughout life in slow-twitch muscles, but only in the developmental and neonatal stages in fast-twitch muscles. CASQ2-/- causes increase in calsequestrin 1 (CASQ1) expression, but without functional changes in both muscle types. CASQ2-/- mice have ultrastructural changes in fast-twitch muscles only, i.e., formation of pentads and stacks in the sarcoplasmic reticulum.
Collapse
Affiliation(s)
- Giorgia Valle
- Dipartimento di Scienze Biomediche dell'Università di Padova, Istituto Interuniversitario di Miologia, Viale G. Colombo 3, 35121, Padova, Italy
| | - Barbara Vergani
- Consorzio MIA (Microscopy Image Analysis), Università di Milano-Bicocca, 20052, Monza, Italy
| | - Roberta Sacchetto
- Dipartimento di Biomedicina Comparata ed Alimentazione dell'Università di Padova, Padova, Italy
| | - Carlo Reggiani
- Dipartimento di Scienze Biomediche dell'Università di Padova, Istituto Interuniversitario di Miologia, Viale G. Colombo 3, 35121, Padova, Italy
| | - Edith De Rosa
- Dipartimento di Scienze Biomediche dell'Università di Padova, Istituto Interuniversitario di Miologia, Viale G. Colombo 3, 35121, Padova, Italy
| | - Lisa Maccatrozzo
- Dipartimento di Biomedicina Comparata ed Alimentazione dell'Università di Padova, Padova, Italy
| | - Alessandra Nori
- Dipartimento di Scienze Biomediche dell'Università di Padova, Istituto Interuniversitario di Miologia, Viale G. Colombo 3, 35121, Padova, Italy
| | - Antonello Villa
- Consorzio MIA (Microscopy Image Analysis), Università di Milano-Bicocca, 20052, Monza, Italy
| | - Pompeo Volpe
- Dipartimento di Scienze Biomediche dell'Università di Padova, Istituto Interuniversitario di Miologia, Viale G. Colombo 3, 35121, Padova, Italy.
| |
Collapse
|
27
|
Calsequestrin depolymerizes when calcium is depleted in the sarcoplasmic reticulum of working muscle. Proc Natl Acad Sci U S A 2017; 114:E638-E647. [PMID: 28069951 DOI: 10.1073/pnas.1620265114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Calsequestrin, the only known protein with cyclical storage and supply of calcium as main role, is proposed to have other functions, which remain unproven. Voluntary movement and the heart beat require this calcium flow to be massive and fast. How does calsequestrin do it? To bind large amounts of calcium in vitro, calsequestrin must polymerize and then depolymerize to release it. Does this rule apply inside the sarcoplasmic reticulum (SR) of a working cell? We answered using fluorescently tagged calsequestrin expressed in muscles of mice. By FRAP and imaging we monitored mobility of calsequestrin as [Ca2+] in the SR--measured with a calsequestrin-fused biosensor--was lowered. We found that calsequestrin is polymerized within the SR at rest and that it depolymerized as [Ca2+] went down: fully when calcium depletion was maximal (a condition achieved with an SR calcium channel opening drug) and partially when depletion was limited (a condition imposed by fatiguing stimulation, long-lasting depolarization, or low drug concentrations). With fluorescence and electron microscopic imaging we demonstrated massive movements of calsequestrin accompanied by drastic morphological SR changes in fully depleted cells. When cells were partially depleted no remodeling was found. The present results support the proposed role of calsequestrin in termination of calcium release by conformationally inducing closure of SR channels. A channel closing switch operated by calsequestrin depolymerization will limit depletion, thereby preventing full disassembly of the polymeric calsequestrin network and catastrophic structural changes in the SR.
Collapse
|
28
|
Witherspoon JW, Meilleur KG. Review of RyR1 pathway and associated pathomechanisms. Acta Neuropathol Commun 2016; 4:121. [PMID: 27855725 PMCID: PMC5114830 DOI: 10.1186/s40478-016-0392-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 11/02/2016] [Indexed: 02/04/2023] Open
Abstract
Ryanodine receptor isoform-1 (RyR1) is a major calcium channel in skeletal muscle important for excitation-contraction coupling. Mutations in the RYR1 gene yield RyR1 protein dysfunction that manifests clinically as RYR1-related congenital myopathies (RYR1-RM) and/or malignant hyperthermia susceptibility (MHS). Individuals with RYR1-RM and/or MHS exhibit varying symptoms and severity. The symptoms impair quality of life and put patients at risk for early mortality, yet the cause of varying severity is not well understood. Currently, there is no Food and Drug Administration (FDA) approved treatment for RYR1-RM. Discovery of effective treatments is therefore critical, requiring knowledge of the RyR1 pathway. The purpose of this review is to compile work published to date on the RyR1 pathway and to implicate potential regions as targets for treatment. The RyR1 pathway is comprised of protein-protein interactions, protein-ligand interactions, and post-translational modifications, creating an activation/regulatory macromolecular complex. Given the complexity of this pathway, we divided these interactions and modifications into six regulatory groups. Three of several RyR1 interacting proteins, FK506-binding protein 12 (FKBP12), triadin, and calmodulin, were identified as playing important roles across all groups and may serve as promising target sites for treatment. Also, variability in disease severity may be influenced by prolongation or hyperactivity of post-translational modifications resulting from RyR1 dysfunction.
Collapse
|
29
|
Samsó M. A guide to the 3D structure of the ryanodine receptor type 1 by cryoEM. Protein Sci 2016; 26:52-68. [PMID: 27671094 DOI: 10.1002/pro.3052] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 01/04/2023]
Abstract
Signal transduction by the ryanodine receptor (RyR) is essential in many excitable cells including all striated contractile cells and some types of neurons. While its transmembrane domain is a classic tetrameric, six-transmembrane cation channel, the cytoplasmic domain is uniquely large and complex, hosting a multiplicity of specialized domains. The overall outline and substructure readily recognizable by electron microscopy make RyR a geometrically well-behaved specimen. Hence, for the last two decades, the 3D structural study of the RyR has tracked closely the technological advances in electron microscopy, cryo-electron microscopy (cryoEM), and computerized 3D reconstruction. This review summarizes the progress in the structural determination of RyR by cryoEM and, bearing in mind the leap in resolution provided by the recent implementation of direct electron detection, analyzes the first near-atomic structures of RyR. These reveal a complex orchestration of domains controlling the channel's function, and help to understand how this could break down as a consequence of disease-causing mutations.
Collapse
Affiliation(s)
- Montserrat Samsó
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, Virginia
| |
Collapse
|
30
|
Three residues in the luminal domain of triadin impact on Trisk 95 activation of skeletal muscle ryanodine receptors. Pflugers Arch 2016; 468:1985-1994. [PMID: 27595738 DOI: 10.1007/s00424-016-1869-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/02/2016] [Accepted: 08/11/2016] [Indexed: 10/21/2022]
Abstract
Triadin isoforms, splice variants of one gene, maintain healthy Ca2+ homeostasis in skeletal muscle by subserving several functions including an influence on Ca2+ release through the ligand-gated ryanodine receptor (RyR1) ion channels. The predominant triadin isoform in skeletal muscle, Trisk 95, activates RyR1 in vitro via binding to previously unidentified amino acids between residues 200 and 232. Here, we identify three amino acids that influence Trisk 95 binding to RyR1 and ion channel activation, using peptides encompassing residues 200-232. Selective alanine substitutions show that K218, K220, and K224 together facilitate normal Trisk 95 binding to RyR1 and channel activation. Neither RyR1 binding nor activation are altered by alanine substitution of K220 alone or of K218 and K224. Therefore K218, K220, and K224 contribute to a robust binding and activation site that is disrupted only when the charge on all three residues is neutralized. We suggest that charged pair interactions between acidic RyR1 residues D4878, D4907, and E4908 and Trisk 95 residues K218, K220, and K224 facilitate Trisk 95 binding to RyR1 and channel activation. Since K218, K220, and K224 are also required for CSQ binding to RyRs (Kobayashi et al. 17, J Biol Chem 275, 17639-17646), the results suggest that Trisk 95 may not simultaneously bind to RyR1 and CSQ, contrary to the widely held belief that triadin monomers form a quaternary complex with junctin, CSQ and RyR1. Therefore, the in vivo role of triadin monomers in modulating RyR1 activity is likely unrelated to CSQ.
Collapse
|
31
|
Rani S, Park CS, Sreenivasaiah PK, Kim DH. Characterization of Ca(2+)-Dependent Protein-Protein Interactions within the Ca(2+) Release Units of Cardiac Sarcoplasmic Reticulum. Mol Cells 2016; 39:149-55. [PMID: 26674963 PMCID: PMC4757803 DOI: 10.14348/molcells.2016.2284] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 11/02/2015] [Accepted: 11/03/2015] [Indexed: 02/04/2023] Open
Abstract
In the heart, excitation-contraction (E-C) coupling is mediated by Ca(2+) release from sarcoplasmic reticulum (SR) through the interactions of proteins forming the Ca(2+) release unit (CRU). Among them, calsequestrin (CSQ) and histidine-rich Ca(2+) binding protein (HRC) are known to bind the charged luminal region of triadin (TRN) and thus directly or indirectly regulate ryanodine receptor 2 (RyR2) activity. However, the mechanisms of CSQ and HRC mediated regulation of RyR2 activity through TRN have remained unclear. We first examined the minimal KEKE motif of TRN involved in the interactions with CSQ2, HRC and RyR2 using TRN deletion mutants and in vitro binding assays. The results showed that CSQ2, HRC and RyR2 share the same KEKE motif region on the distal part of TRN (aa 202-231). Second, in vitro binding assays were conducted to examine the Ca(2+) dependence of protein-protein interactions (PPI). The results showed that TRN-HRC interaction had a bell-shaped Ca(2+) dependence, which peaked at pCa4, whereas TRN-CSQ2 or TRN-RyR2 interaction did not show such Ca(2+) dependence pattern. Third, competitive binding was conducted to examine whether CSQ2, HRC, or RyR2 affects the TRN-HRC or TRN-CSQ2 binding at pCa4. Among them, only CSQ2 or RyR2 competitively inhibited TRN-HRC binding, suggesting that HRC can confer functional refractoriness to CRU, which could be beneficial for reloading of Ca(2+) into SR at intermediate Ca(2+) concentrations.
Collapse
Affiliation(s)
- Shilpa Rani
- School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology, Gwangju 500-712,
Korea
| | - Chang Sik Park
- School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology, Gwangju 500-712,
Korea
| | - Pradeep Kumar Sreenivasaiah
- School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology, Gwangju 500-712,
Korea
| | - Do Han Kim
- School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology, Gwangju 500-712,
Korea
| |
Collapse
|
32
|
Perni S, Close M, Franzini-Armstrong C. Design Principles of Reptilian Muscles: Calcium Cycling Strategies. Anat Rec (Hoboken) 2015; 299:352-60. [PMID: 26663776 DOI: 10.1002/ar.23302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/08/2015] [Accepted: 10/29/2015] [Indexed: 11/07/2022]
Abstract
The ultrastructure of the sarcoplasmic reticulum (SR) in skeletal muscles was compared among different reptile species (watersnake, boa constrictor, lizard, and turtle) and a mammal (mouse). Morphometric analysis demonstrates a pattern of increasing calsequestrin (CASQ) content in the lumen of SR from turtle to lizard, watersnake, and boa constrictor, and this content is in all cases higher than in mouse. In all reptiles sampled except turtle, CASQ is not confined to the junctional sarcoplasmic reticulum (jSR) cisternae as it is in other species. It instead fills the entire longitudinal (free) SR (fSR) regions, and in the extreme case of snakes, the shape of the SR is modified around the extra CASQ. We suggest that high CASQ content may represent an ATP-saving adaptation that permits relatively low metabolic rates during prolonged periods of fasting and inactivity, particularly in watersnake and boa constrictor.
Collapse
Affiliation(s)
- Stefano Perni
- Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Matthew Close
- Department of Biological Sciences, Williams Annex., Lehigh University, Bethlehem, Pennsylvania
| | - Clara Franzini-Armstrong
- Department of Cell and Developmental Biology, University of Pennsylvania, Philadelphia, Pennsylvania
| |
Collapse
|
33
|
Schils S, Carraro U, Turner T, Ravara B, Gobbo V, Kern H, Gelbmann L, Pribyl J. Functional Electrical Stimulation for Equine Muscle Hypertonicity: Histological Changes in Mitochondrial Density and Distribution. J Equine Vet Sci 2015. [DOI: 10.1016/j.jevs.2015.08.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
34
|
Jayasinghe ID, Munro M, Baddeley D, Launikonis BS, Soeller C. Observation of the molecular organization of calcium release sites in fast- and slow-twitch skeletal muscle with nanoscale imaging. J R Soc Interface 2015; 11:rsif.2014.0570. [PMID: 25100314 DOI: 10.1098/rsif.2014.0570] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Localization microscopy is a fairly recently introduced super-resolution fluorescence imaging modality capable of achieving nanometre-scale resolution. We have applied the dSTORM variation of this method to image intracellular molecular assemblies in skeletal muscle fibres which are large cells that critically rely on nanoscale signalling domains, the triads. Immunofluorescence staining in fixed adult rat skeletal muscle sections revealed clear differences between fast- and slow-twitch fibres in the molecular organization of ryanodine receptors (RyRs; the primary calcium release channels) within triads. With the improved resolution offered by dSTORM, abutting arrays of RyRs in transverse view of fast fibres were observed in contrast to the fragmented distribution on slow-twitch muscle that were approximately 1.8 times shorter and consisted of approximately 1.6 times fewer receptors. To the best of our knowledge, for the first time, we have quantified the nanometre-scale spatial association between triadic proteins using multi-colour super-resolution, an analysis difficult to conduct with electron microscopy. Our findings confirm that junctophilin-1 (JPH1), which tethers the sarcoplasmic reticulum ((SR) intracellular calcium store) to the tubular (t-) system at triads, was present throughout the RyR array, whereas JPH2 was contained within much smaller nanodomains. Similar imaging of the primary SR calcium buffer, calsequestrin (CSQ), detected less overlap of the triad with CSQ in slow-twitch muscle supporting greater spatial heterogeneity in the luminal Ca2+ buffering when compared with fast twitch muscle. Taken together, these nanoscale differences can explain the fundamentally different physiologies of fast- and slow-twitch muscle.
Collapse
Affiliation(s)
- Isuru D Jayasinghe
- School of Biomedical Science, The University of Queensland, Brisbane, Queensland, Australia College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK
| | - Michelle Munro
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - David Baddeley
- Department of Physiology, The University of Auckland, Auckland, New Zealand Department of Cell Biology, Yale University, New Haven, CT, USA
| | - Bradley S Launikonis
- School of Biomedical Science, The University of Queensland, Brisbane, Queensland, Australia
| | - Christian Soeller
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter, UK Department of Physiology, The University of Auckland, Auckland, New Zealand
| |
Collapse
|
35
|
Song X, Tang Y, Lei C, Cao M, Shen Y, Yang Y. In situ visualizing T-Tubule/SR junction reveals the ultra-structures of calcium storage and release machinery. Int J Biol Macromol 2015; 82:7-12. [PMID: 26454109 DOI: 10.1016/j.ijbiomac.2015.10.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 10/01/2015] [Accepted: 10/05/2015] [Indexed: 10/22/2022]
Abstract
In skeletal muscle, Ca(2+) release from sarcoplasmic reticulum (SR) following the action potential relies on the delicate architecture of the T-Tubule/SR junction. The T-Tubule/SR junction comprises two membrane systems: the integral proteins DHPR and RyR1 and the Ca(2+)-buffering apparatus within the SR lumen. The arrangement and interactions of the components have remained elusive due to technological limitations. Here, we determined whether electron tomography is effective fort the in situ determination of the relationships between RyR1 and DHPR, the SR membrane and other involved structures. First, we visually confirmed that RyR1 and DHPR are close neighbors that are mutually staggered with each other and directly interact with one of RyR1 subunits. Second, the Ca(2+) storage network within the SR lumen is directly correlated with RyR1. These results suggest that the excitation of the T-Tubule may induce Ca(2+) release through a direct interaction among DHPR, RyR1 and the Ca(2+) buffering apparatus. These results indicate that electron tomography has potential as an efficient method for the in situ characterization of the complex architecture and arrangement of two integral-integral-membrane proteins in the context of the surrounding phospholipid-bilayer and proteins.
Collapse
Affiliation(s)
- XiaoWei Song
- Department of Biophysics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China
| | - Ying Tang
- Department of Biophysics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China
| | - ChangHai Lei
- Department of Biophysics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China
| | - Mi Cao
- Department of Biophysics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China
| | - YaFeng Shen
- Department of Biophysics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China
| | - YongJi Yang
- Department of Biophysics, Second Military Medical University, 800 Xiangyin Road, Shanghai 200433, China.
| |
Collapse
|
36
|
Lewis KM, Ronish LA, Ríos E, Kang C. Characterization of Two Human Skeletal Calsequestrin Mutants Implicated in Malignant Hyperthermia and Vacuolar Aggregate Myopathy. J Biol Chem 2015; 290:28665-74. [PMID: 26416891 DOI: 10.1074/jbc.m115.686261] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Indexed: 12/14/2022] Open
Abstract
Calsequestrin 1 is the principal Ca(2+) storage protein of the sarcoplasmic reticulum of skeletal muscle. Its inheritable D244G mutation causes a myopathy with vacuolar aggregates, whereas its M87T "variant" is weakly associated with malignant hyperthermia. We characterized the consequences of these mutations with studies of the human proteins in vitro. Equilibrium dialysis and turbidity measurements showed that D244G and, to a lesser extent, M87T partially lose Ca(2+) binding exhibited by wild type calsequestrin 1 at high Ca(2+) concentrations. D244G aggregates abruptly and abnormally, a property that fully explains the protein inclusions that characterize its phenotype. D244G crystallized in low Ca(2+) concentrations lacks two Ca(2+) ions normally present in wild type that weakens the hydrophobic core of Domain II. D244G crystallized in high Ca(2+) concentrations regains its missing ions and Domain II order but shows a novel dimeric interaction. The M87T mutation causes a major shift of the α-helix bearing the mutated residue, significantly weakening the back-to-back interface essential for tetramerization. D244G exhibited the more severe structural and biophysical property changes, which matches the different pathophysiological impacts of these mutations.
Collapse
Affiliation(s)
- Kevin M Lewis
- From the Department of Chemistry, Washington State University, Pullman, Washington 99164-4630
| | - Leslie A Ronish
- School of Molecular Biosciences, Washington State University, Pullman, Washington 99164-4660, and
| | - Eduardo Ríos
- Department of Molecular Biophysics and Physiology, Rush University, Chicago, Illinois 60612
| | - ChulHee Kang
- From the Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, School of Molecular Biosciences, Washington State University, Pullman, Washington 99164-4660, and
| |
Collapse
|
37
|
Organization of junctional sarcoplasmic reticulum proteins in skeletal muscle fibers. J Muscle Res Cell Motil 2015; 36:501-15. [DOI: 10.1007/s10974-015-9421-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 09/08/2015] [Indexed: 01/24/2023]
|
38
|
Kern H, Jakubiec-Puka A, Carraro U. Editorial: The EJTM Special "Mobility in Elderly". Eur J Transl Myol 2015; 25:208-13. [PMID: 26913158 PMCID: PMC4748983 DOI: 10.4081/ejtm.2015.5412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Not available.
Collapse
|
39
|
Di Blasi C, Sansanelli S, Ruggieri A, Moriggi M, Vasso M, D'Adamo AP, Blasevich F, Zanotti S, Paolini C, Protasi F, Tezzon F, Gelfi C, Morandi L, Pessia M, Mora M. A CASQ1 founder mutation in three Italian families with protein aggregate myopathy and hyperCKaemia. J Med Genet 2015; 52:617-26. [PMID: 26136523 DOI: 10.1136/jmedgenet-2014-102882] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 06/16/2015] [Indexed: 12/24/2022]
Abstract
BACKGROUND Protein aggregate myopathies are increasingly recognised conditions characterised by a surplus of endogenous proteins. The molecular and mutational background for many protein aggregate myopathies has been clarified with the discovery of several underlying mutations. Familial idiopathic hyperCKaemia is a benign genetically heterogeneous condition with autosomal dominant features in a high proportion of cases. METHODS In 10 patients from three Italian families with autosomal dominant benign vacuolar myopathy and hyperCKaemia, we performed linkage analysis and exome sequencing as well as morphological and biochemical investigations. RESULTS AND CONCLUSIONS We show, by Sanger and exome sequencing, that the protein aggregate myopathy with benign evolution and muscle inclusions composed of excess CASQ1, affecting three Italian families, is due to the D244G heterozygous missense mutation in the CASQ1 gene. Investigation of microsatellite markers revealed a common haplotype in the three families indicating consanguinity and a founder effect. Results from immunocytochemistry, electron microscopy, biochemistry and transfected cell line investigations contribute to our understanding of pathogenetic mechanisms underlining this defect. The mutation is common to other Italian patients and is likely to share a founder effect with them. HyperCKaemia in the CASQ1-related myopathy is common and sometimes the sole overt manifestation. It is likely that CASQ1 mutations may remain undiagnosed if a muscle biopsy is not performed, and the condition could be more common than supposed.
Collapse
Affiliation(s)
- Claudia Di Blasi
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| | - Serena Sansanelli
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| | - Alessandra Ruggieri
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| | - Manuela Moriggi
- Department of Biomedical Sciences for Health, University of Milano, Milano, Italy
| | - Michele Vasso
- Department of Biomedical Sciences for Health, University of Milano, Milano, Italy CNR-Institute of Bioimaging and Molecular Physiology, Milano, Italy
| | | | - Flavia Blasevich
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| | - Simona Zanotti
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| | - Cecilia Paolini
- CeSI, Center for Research on Ageing & Department of Neuroscience, Imaging, and Clinical Sciences, University G D'Annunzio of Chieti, Chieti, Italy
| | - Feliciano Protasi
- CeSI, Center for Research on Ageing & Department of Neuroscience, Imaging, and Clinical Sciences, University G D'Annunzio of Chieti, Chieti, Italy
| | - Frediano Tezzon
- Neurology Unit, F Tappeiner Hospital of Merano, Merano, Italy
| | - Cecilia Gelfi
- Department of Biomedical Sciences for Health, University of Milano, Milano, Italy CNR-Institute of Bioimaging and Molecular Physiology, Milano, Italy
| | - Lucia Morandi
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| | - Mauro Pessia
- Faculty of Medicine, Section of Physiology and Biochemistry, Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Marina Mora
- Neuromuscular Diseases and Neuroimmunology Unit, Foundation IRCCS Neurological Institute C. Besta, Milano, Italy
| |
Collapse
|
40
|
Beard NA, Dulhunty AF. C-terminal residues of skeletal muscle calsequestrin are essential for calcium binding and for skeletal ryanodine receptor inhibition. Skelet Muscle 2015; 5:6. [PMID: 25861445 PMCID: PMC4389316 DOI: 10.1186/s13395-015-0029-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 01/14/2015] [Indexed: 02/05/2023] Open
Abstract
Background Skeletal muscle function depends on calcium signaling proteins in the sarcoplasmic reticulum (SR), including the calcium-binding protein calsequestrin (CSQ), the ryanodine receptor (RyR) calcium release channel, and skeletal triadin 95 kDa (trisk95) and junctin, proteins that bind to calsequestrin type 1 (CSQ1) and ryanodine receptor type 1 (RyR1). CSQ1 inhibits RyR1 and communicates store calcium load to RyR1 channels via trisk95 and/or junctin. Methods In this manuscript, we test predictions that CSQ1’s acidic C-terminus contains binding sites for trisk95 and junctin, the major calcium binding domain, and that it determines CSQ1’s ability to regulate RyR1 activity. Results Progressive alanine substitution of C-terminal acidic residues of CSQ1 caused a parallel reduction in the calcium binding capacity but did not significantly alter CSQ1’s association with trisk95/junctin or influence its inhibition of RyR1 activity. Deletion of the final seven residues in the C-terminus significantly hampered calcium binding, significantly reduced CSQ’s association with trisk95/junctin and decreased its inhibition of RyR1. Deletion of the full C-terminus further reduced calcium binding to CSQ1 altered its association with trisk95 and junctin and abolished its inhibition of RyR1. Conclusions The correlation between the number of residues mutated/deleted and binding of calcium, trisk95, and junctin suggests that binding of each depends on diffuse ionic interactions with several C-terminal residues and that these interactions may be required for CSQ1 to maintain normal muscle function.
Collapse
Affiliation(s)
- Nicole A Beard
- John Curtin School of Medical Research, Australian National University, Garran Road, Canberra, ACT 2601 Australia ; Discipline of Biomedical Sciences, Centre for Research in Therapeutic Solutions, Faculty of Education Science, Technology and Maths, University of Canberra, Kirinari Street, Bruce, ACT 2601 Australia
| | - Angela F Dulhunty
- John Curtin School of Medical Research, Australian National University, Garran Road, Canberra, ACT 2601 Australia
| |
Collapse
|
41
|
Li L, Mirza S, Richardson SJ, Gallant EM, Thekkedam C, Pace SM, Zorzato F, Liu D, Beard NA, Dulhunty AF. A new cytoplasmic interaction between junctin and ryanodine receptor Ca2+ release channels. J Cell Sci 2015; 128:951-63. [PMID: 25609705 PMCID: PMC4342579 DOI: 10.1242/jcs.160689] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Junctin, a non-catalytic splice variant encoded by the aspartate-β-hydroxylase (Asph) gene, is inserted into the membrane of the sarcoplasmic reticulum (SR) Ca2+ store where it modifies Ca2+ signalling in the heart and skeletal muscle through its regulation of ryanodine receptor (RyR) Ca2+ release channels. Junctin is required for normal muscle function as its knockout leads to abnormal Ca2+ signalling, muscle dysfunction and cardiac arrhythmia. However, the nature of the molecular interaction between junctin and RyRs is largely unknown and was assumed to occur only in the SR lumen. We find that there is substantial binding of RyRs to full junctin, and the junctin luminal and, unexpectedly, cytoplasmic domains. Binding of these different junctin domains had distinct effects on RyR1 and RyR2 activity: full junctin in the luminal solution increased RyR channel activity by ∼threefold, the C-terminal luminal interaction inhibited RyR channel activity by ∼50%, and the N-terminal cytoplasmic binding produced an ∼fivefold increase in RyR activity. The cytoplasmic interaction between junctin and RyR is required for luminal binding to replicate the influence of full junctin on RyR1 and RyR2 activity. The C-terminal domain of junctin binds to residues including the S1–S2 linker of RyR1 and N-terminal domain of junctin binds between RyR1 residues 1078 and 2156.
Collapse
Affiliation(s)
- Linwei Li
- John Curtin School of Medical Research, ACT 0200, Australia
| | - Shamaruh Mirza
- John Curtin School of Medical Research, ACT 0200, Australia
| | | | | | | | - Suzy M Pace
- John Curtin School of Medical Research, ACT 0200, Australia
| | | | - Dan Liu
- John Curtin School of Medical Research, ACT 0200, Australia
| | - Nicole A Beard
- John Curtin School of Medical Research, ACT 0200, Australia
| | | |
Collapse
|
42
|
Myoplasmic resting Ca2+ regulation by ryanodine receptors is under the control of a novel Ca2+-binding region of the receptor. Biochem J 2014; 460:261-71. [PMID: 24635445 PMCID: PMC4019983 DOI: 10.1042/bj20131553] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Passive SR (sarcoplasmic reticulum) Ca2+ leak through the RyR (ryanodine receptor) plays a critical role in the mechanisms that regulate [Ca2+]rest (intracellular resting myoplasmic free Ca2+ concentration) in muscle. This process appears to be isoform-specific as expression of either RyR1 or RyR3 confers on myotubes different [Ca2+]rest. Using chimaeric RyR3–RyR1 receptors expressed in dyspedic myotubes, we show that isoform-dependent regulation of [Ca2+]rest is primarily defined by a small region of the receptor encompassing amino acids 3770–4007 of RyR1 (amino acids 3620–3859 of RyR3) named as the CLR (Ca2+ leak regulatory) region. [Ca2+]rest regulation by the CLR region was associated with alteration of RyRs’ Ca2+-activation profile and changes in SR Ca2+-leak rates. Biochemical analysis using Tb3+-binding assays and intrinsic tryptophan fluorescence spectroscopy of purified CLR domains revealed that this determinant of RyRs holds a novel Ca2+-binding domain with conformational properties that are distinctive to each isoform. Our data suggest that the CLR region provides channels with unique functional properties that modulate the rate of passive SR Ca2+ leak and confer on RyR1 and RyR3 distinctive [Ca2+]rest regulatory properties. The identification of a new Ca2+-binding domain of RyRs with a key modulatory role in [Ca2+]rest regulation provides new insights into Ca2+-mediated regulation of RyRs. This paper reports the finding of a new class of Ca2+-binding domain of intracellular Ca2+ channels from muscle cells. This domain provides channels with distinctive properties that result in channel-specific modulation of the intracellular resting Ca2+ concentration.
Collapse
|
43
|
Editors T. CIR-Myo News: Proceedings of the 2014 Spring Padua Muscle Days: Terme Euganee and Padova (Italy), April 3-5, 2014. Eur J Transl Myol 2014; 24:3299. [PMID: 26913130 PMCID: PMC4749006 DOI: 10.4081/ejtm.2014.3299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Not available.
Collapse
|
44
|
Carraro U, Coletti D, Kern H. The Ejtm Specials "The Long-Term Denervated Muscle". Eur J Transl Myol 2014; 24:3292. [PMID: 26913124 PMCID: PMC4749000 DOI: 10.4081/ejtm.2014.3292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
|
45
|
Calderón JC, Bolaños P, Caputo C. The excitation-contraction coupling mechanism in skeletal muscle. Biophys Rev 2014; 6:133-160. [PMID: 28509964 PMCID: PMC5425715 DOI: 10.1007/s12551-013-0135-x] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 12/06/2013] [Indexed: 12/27/2022] Open
Abstract
First coined by Alexander Sandow in 1952, the term excitation-contraction coupling (ECC) describes the rapid communication between electrical events occurring in the plasma membrane of skeletal muscle fibres and Ca2+ release from the SR, which leads to contraction. The sequence of events in twitch skeletal muscle involves: (1) initiation and propagation of an action potential along the plasma membrane, (2) spread of the potential throughout the transverse tubule system (T-tubule system), (3) dihydropyridine receptors (DHPR)-mediated detection of changes in membrane potential, (4) allosteric interaction between DHPR and sarcoplasmic reticulum (SR) ryanodine receptors (RyR), (5) release of Ca2+ from the SR and transient increase of Ca2+ concentration in the myoplasm, (6) activation of the myoplasmic Ca2+ buffering system and the contractile apparatus, followed by (7) Ca2+ disappearance from the myoplasm mediated mainly by its reuptake by the SR through the SR Ca2+ adenosine triphosphatase (SERCA), and under several conditions movement to the mitochondria and extrusion by the Na+/Ca2+ exchanger (NCX). In this text, we review the basics of ECC in skeletal muscle and the techniques used to study it. Moreover, we highlight some recent advances and point out gaps in knowledge on particular issues related to ECC such as (1) DHPR-RyR molecular interaction, (2) differences regarding fibre types, (3) its alteration during muscle fatigue, (4) the role of mitochondria and store-operated Ca2+ entry in the general ECC sequence, (5) contractile potentiators, and (6) Ca2+ sparks.
Collapse
Affiliation(s)
- Juan C Calderón
- Physiology and Biochemistry Research Group-Physis, Department of Physiology and Biochemistry, Faculty of Medicine, University of Antioquia UdeA, Calle 70 No 52-21, Medellín, Colombia.
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela.
- Departamento de Fisiología y Bioquímica, Grupo de Investigación en Fisiología y Bioquímica-Physis, Facultad de Medicina, Universidad de Antioquia, Calle 70 No 52-21, Medellín, Colombia.
| | - Pura Bolaños
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| | - Carlo Caputo
- Laboratory of Cellular Physiology, Centre of Biophysics and Biochemistry, Venezuelan Institute for Scientific Research (IVIC), Caracas, Venezuela
| |
Collapse
|
46
|
Rebbeck RT, Karunasekara Y, Board PG, Beard NA, Casarotto MG, Dulhunty AF. Skeletal muscle excitation–contraction coupling: Who are the dancing partners? Int J Biochem Cell Biol 2014; 48:28-38. [DOI: 10.1016/j.biocel.2013.12.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Revised: 11/29/2013] [Accepted: 12/04/2013] [Indexed: 01/15/2023]
|
47
|
Distinct regions of triadin are required for targeting and retention at the junctional domain of the sarcoplasmic reticulum. Biochem J 2014; 458:407-17. [DOI: 10.1042/bj20130719] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Three regions contribute to triadin localization to the junctional sarcoplasmic reticulum. Dynamics studies revealed that TR3 mediates triadin stability at junctional sites. The stable association of triadin at the junctional sites is facilitated by interactions with calsequestrin-1.
Collapse
|
48
|
Perni S, Close M, Franzini-Armstrong C. Novel details of calsequestrin gel conformation in situ. J Biol Chem 2013; 288:31358-62. [PMID: 24025332 DOI: 10.1074/jbc.m113.507749] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Calsequestrin (CASQ) is the major component of the sarcoplasmic reticulum (SR) lumen in skeletal and cardiac muscles. This calcium-binding protein localizes to the junctional SR (jSR) cisternae, where it is responsible for the storage of large amounts of Ca(2+), whereas it is usually absent, at least in its polymerized form, in the free SR. The retention of CASQ inside the jSR is due partly to its association with other jSR proteins, such as junctin and triadin, and partly to its ability to polymerize, in a high Ca(2+) environment, into an intricate gel that holds the protein in place. In this work, we shed some light on the still poorly described in situ structure of polymerized CASQ using detailed EM images from thin sections, with and without tilting, and from deep-etched rotary-shadowed replicas. The latter directly illustrate the fundamental network nature of polymerized CASQ, revealing repeated nodal points connecting short segments of the linear polymer.
Collapse
Affiliation(s)
- Stefano Perni
- From the Department of Cell Developmental Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6058 and
| | | | | |
Collapse
|
49
|
Manno C, Figueroa L, Royer L, Pouvreau S, Lee CS, Volpe P, Nori A, Zhou J, Meissner G, Hamilton SL, Ríos E. Altered Ca2+ concentration, permeability and buffering in the myofibre Ca2+ store of a mouse model of malignant hyperthermia. J Physiol 2013; 591:4439-57. [PMID: 23798496 DOI: 10.1113/jphysiol.2013.259572] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Malignant hyperthermia (MH) is linked to mutations in the type 1 ryanodine receptor, RyR1, the Ca2+ channel of the sarcoplasmic reticulum (SR) of skeletal muscle. The Y522S MH mutation was studied for its complex presentation, which includes structurally and functionally altered cell 'cores'. Imaging cytosolic and intra-SR [Ca2+] in muscle cells of heterozygous YS mice we determined Ca2+ release flux activated by clamp depolarization, permeability (P) of the SR membrane (ratio of flux and [Ca2+] gradient) and SR Ca2+ buffering power (B). In YS cells resting [Ca2+]SR was 45% of the value in normal littermates (WT). P was more than doubled, so that initial flux was normal. Measuring [Ca2+]SR(t) revealed dynamic changes in B(t). The alterations were similar to those caused by cytosolic BAPTA, which promotes release by hampering Ca2+-dependent inactivation (CDI). The [Ca2+] transients showed abnormal 'breaks', decaying phases after an initial rise, traced to a collapse in flux and P. Similar breaks occurred in WT myofibres with calsequestrin reduced by siRNA; calsequestrin content, however, was normal in YS muscle. Thus, the Y522S mutation causes greater openness of the RyR1, lowers resting [Ca2+]SR and alters SR Ca2+ buffering in a way that copies the functional instability observed upon reduction of calsequestrin content. The similarities with the effects of BAPTA suggest that the mutation, occurring near the cytosolic vestibule of the channel, reduces CDI as one of its primary effects. The unstable SR buffering, mimicked by silencing of calsequestrin, may help precipitate the loss of Ca2+ control that defines a fulminant MH event.
Collapse
Affiliation(s)
- Carlo Manno
- S. L. Hamilton: ; E. Ríos: Rush University School of Medicine, Department of Molecular Biophysics and Physiology, 1750 West Harrison St., Suite 1279JS, Chicago, IL 60612, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|