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Dowling P, Swandulla D, Ohlendieck K. Biochemical and proteomic insights into sarcoplasmic reticulum Ca 2+-ATPase complexes in skeletal muscles. Expert Rev Proteomics 2023; 20:125-142. [PMID: 37668143 DOI: 10.1080/14789450.2023.2255743] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 07/07/2023] [Accepted: 08/14/2023] [Indexed: 09/06/2023]
Abstract
INTRODUCTION Skeletal muscles contain large numbers of high-molecular-mass protein complexes in elaborate membrane systems. Integral membrane proteins are involved in diverse cellular functions including the regulation of ion handling, membrane homeostasis, energy metabolism and force transmission. AREAS COVERED The proteomic profiling of membrane proteins and large protein assemblies in skeletal muscles are outlined in this article. This includes a critical overview of the main biochemical separation techniques and the mass spectrometric approaches taken to study membrane proteins. As an illustrative example of an analytically challenging large protein complex, the proteomic detection and characterization of the Ca2+-ATPase of the sarcoplasmic reticulum is discussed. The biological role of this large protein complex during normal muscle functioning, in the context of fiber type diversity and in relation to mechanisms of physiological adaptations and pathophysiological abnormalities is evaluated from a proteomics perspective. EXPERT OPINION Mass spectrometry-based muscle proteomics has decisively advanced the field of basic and applied myology. Although it is technically challenging to study membrane proteins, innovations in protein separation methodology in combination with sensitive mass spectrometry and improved systems bioinformatics has allowed the detailed proteomic detection and characterization of skeletal muscle membrane protein complexes, such as Ca2+-pump proteins of the sarcoplasmic reticulum.
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Affiliation(s)
- Paul Dowling
- Department of Biology, Maynooth University, National University of Ireland, Maynooth Kildare, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, Maynooth Kildare, Ireland
| | - Dieter Swandulla
- Institute of Physiology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Kay Ohlendieck
- Department of Biology, Maynooth University, National University of Ireland, Maynooth Kildare, Ireland
- Kathleen Lonsdale Institute for Human Health Research, Maynooth University, Maynooth Kildare, Ireland
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Woo JS, Jeong SY, Park JH, Choi JH, Lee EH. Calsequestrin: a well-known but curious protein in skeletal muscle. Exp Mol Med 2020; 52:1908-1925. [PMID: 33288873 PMCID: PMC8080761 DOI: 10.1038/s12276-020-00535-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/14/2020] [Accepted: 10/19/2020] [Indexed: 12/23/2022] Open
Abstract
Calsequestrin (CASQ) was discovered in rabbit skeletal muscle tissues in 1971 and has been considered simply a passive Ca2+-buffering protein in the sarcoplasmic reticulum (SR) that provides Ca2+ ions for various Ca2+ signals. For the past three decades, physiologists, biochemists, and structural biologists have examined the roles of the skeletal muscle type of CASQ (CASQ1) in skeletal muscle and revealed that CASQ1 has various important functions as (1) a major Ca2+-buffering protein to maintain the SR with a suitable amount of Ca2+ at each moment, (2) a dynamic Ca2+ sensor in the SR that regulates Ca2+ release from the SR to the cytosol, (3) a structural regulator for the proper formation of terminal cisternae, (4) a reverse-directional regulator of extracellular Ca2+ entries, and (5) a cause of human skeletal muscle diseases. This review is focused on understanding these functions of CASQ1 in the physiological or pathophysiological status of skeletal muscle.
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Affiliation(s)
- Jin Seok Woo
- Department of Physiology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 10833, USA
| | - Seung Yeon Jeong
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, 06591, Korea
- Department of Biomedicine & Health Sciences, Graduate School, The Catholic University of Korea, Seoul, 06591, Korea
| | - Ji Hee Park
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, 06591, Korea
- Department of Biomedicine & Health Sciences, Graduate School, The Catholic University of Korea, Seoul, 06591, Korea
| | - Jun Hee Choi
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, 06591, Korea
- Department of Biomedicine & Health Sciences, Graduate School, The Catholic University of Korea, Seoul, 06591, Korea
| | - Eun Hui Lee
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, 06591, Korea.
- Department of Biomedicine & Health Sciences, Graduate School, The Catholic University of Korea, Seoul, 06591, Korea.
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Park JW, Lee JH, Kim SW, Han JS, Kang KS, Kim SJ, Park TS. Muscle differentiation induced up-regulation of calcium-related gene expression in quail myoblasts. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2018; 31:1507-1515. [PMID: 29879808 PMCID: PMC6127575 DOI: 10.5713/ajas.18.0302] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 05/29/2018] [Indexed: 11/27/2022]
Abstract
Objective In the poultry industry, the most important economic traits are meat quality and carcass yield. Thus, many studies were conducted to investigate the regulatory pathways during muscle differentiation. To gain insight of muscle differentiation mechanism during growth period, we identified and validated calcium-related genes which were highly expressed during muscle differentiation through mRNA sequencing analysis. Methods We conducted next-generation-sequencing (NGS) analysis of mRNA from undifferentiated QM7 cells and differentiated QM7 cells (day 1 to day 3 of differentiation periods). Subsequently, we obtained calcium related genes related to muscle differentiation process and examined the expression patterns by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Results Through RNA sequencing analysis, we found that the transcription levels of six genes (troponin C1, slow skeletal and cardiac type [TNNC1], myosin light chain 1 [MYL1], MYL3, phospholamban [PLN], caveolin 3 [CAV3], and calsequestrin 2 [CASQ2]) particularly related to calcium regulation were gradually increased according to days of myotube differentiation. Subsequently, we validated the expression patterns of calcium-related genes in quail myoblasts. These results indicated that TNNC1, MYL1, MYL3, PLN, CAV3, CASQ2 responded to differentiation and growth performance in quail muscle. Conclusion These results indicated that calcium regulation might play a critical role in muscle differentiation. Thus, these findings suggest that further studies would be warranted to investigate the role of calcium ion in muscle differentiation and could provide a useful biomarker for muscle differentiation and growth.
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Affiliation(s)
- Jeong-Woong Park
- Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea
| | - Jeong Hyo Lee
- Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea
| | - Seo Woo Kim
- Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Korea
| | - Ji Seon Han
- Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Korea
| | - Kyung Soo Kang
- Bio Division, Medikinetics, Inc., Pyeongtaek 17792, Korea
| | - Sung-Jo Kim
- Division of Cosmetics and Biotechnology, Hoseo University, Asan 31499, Korea
| | - Tae Sub Park
- Institute of Green-Bio Science and Technology, Seoul National University, Pyeongchang 25354, Korea.,Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Korea
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Ca2+-dependent regulations and signaling in skeletal muscle: from electro-mechanical coupling to adaptation. Int J Mol Sci 2015; 16:1066-95. [PMID: 25569087 PMCID: PMC4307291 DOI: 10.3390/ijms16011066] [Citation(s) in RCA: 110] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 12/22/2014] [Indexed: 01/07/2023] Open
Abstract
Calcium (Ca2+) plays a pivotal role in almost all cellular processes and ensures the functionality of an organism. In skeletal muscle fibers, Ca(2+) is critically involved in the innervation of skeletal muscle fibers that results in the exertion of an action potential along the muscle fiber membrane, the prerequisite for skeletal muscle contraction. Furthermore and among others, Ca(2+) regulates also intracellular processes, such as myosin-actin cross bridging, protein synthesis, protein degradation and fiber type shifting by the control of Ca(2+)-sensitive proteases and transcription factors, as well as mitochondrial adaptations, plasticity and respiration. These data highlight the overwhelming significance of Ca(2+) ions for the integrity of skeletal muscle tissue. In this review, we address the major functions of Ca(2+) ions in adult muscle but also highlight recent findings of critical Ca(2+)-dependent mechanisms essential for skeletal muscle-regulation and maintenance.
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Tomasi M, Canato M, Paolini C, Dainese M, Reggiani C, Volpe P, Protasi F, Nori A. Calsequestrin (CASQ1) rescues function and structure of calcium release units in skeletal muscles of CASQ1-null mice. Am J Physiol Cell Physiol 2011; 302:C575-86. [PMID: 22049211 DOI: 10.1152/ajpcell.00119.2011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Amplitude of Ca(2+) transients, ultrastructure of Ca(2+) release units, and molecular composition of sarcoplasmic reticulum (SR) are altered in fast-twitch skeletal muscles of calsequestrin-1 (CASQ1)-null mice. To determine whether such changes are directly caused by CASQ1 ablation or are instead the result of adaptive mechanisms, here we assessed ability of CASQ1 in rescuing the null phenotype. In vivo reintroduction of CASQ1 was carried out by cDNA electro transfer in flexor digitorum brevis muscle of the mouse. Exogenous CASQ1 was found to be correctly targeted to the junctional SR (jSR), as judged by immunofluorescence and confocal microscopy; terminal cisternae (TC) lumen was filled with electron dense material and its width was significantly increased, as judged by electron microscopy; peak amplitude of Ca(2+) transients was significantly increased compared with null muscle fibers transfected only with green fluorescent protein (control); and finally, transfected fibers were able to sustain cytosolic Ca(2+) concentration during prolonged tetanic stimulation. Only the expression of TC proteins, such as calsequestrin 2, sarcalumenin, and triadin, was not rescued as judged by Western blot. Thus our results support the view that CASQ1 plays a key role in both Ca(2+) homeostasis and TC structure.
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Affiliation(s)
- Mirta Tomasi
- Dept. of Experimental Biomedical Sciences, Univ. of Padova, Italy
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Novák P, Soukup T. Calsequestrin distribution, structure and function, its role in normal and pathological situations and the effect of thyroid hormones. Physiol Res 2011; 60:439-52. [PMID: 21401301 DOI: 10.33549/physiolres.931989] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Calsequestrin is the main calcium binding protein of the sarcoplasmic reticulum, serving as an important regulator of Ca(2+). In mammalian muscles, it exists as a skeletal isoform found in fast- and slow-twitch skeletal muscles and a cardiac isoform expressed in the heart and slow-twitch muscles. Recently, many excellent reviews that summarised in great detail various aspects of the calsequestrin structure, localisation or function both in skeletal and cardiac muscle have appeared. The present review focuses on skeletal muscle: information on cardiac tissue is given, where differences between both tissues are functionally important. The article reviews the known multiple roles of calsequestrin including pathology in order to introduce this topic to the broader scientific community and to stimulate an interest in this protein. Newly we describe our results on the effect of thyroid hormones on skeletal and cardiac calsequestrin expression and discuss them in the context of available literary data on this topic.
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Affiliation(s)
- P Novák
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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Ohlendieck K. Proteomics of skeletal muscle glycolysis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2010; 1804:2089-101. [DOI: 10.1016/j.bbapap.2010.08.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Revised: 08/01/2010] [Accepted: 08/05/2010] [Indexed: 10/19/2022]
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Vitadello M, Doria A, Tarricone E, Ghirardello A, Gorza L. Myofiber stress-response in myositis: parallel investigations on patients and experimental animal models of muscle regeneration and systemic inflammation. Arthritis Res Ther 2010; 12:R52. [PMID: 20334640 PMCID: PMC2888201 DOI: 10.1186/ar2963] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 01/08/2010] [Accepted: 03/24/2010] [Indexed: 12/17/2022] Open
Abstract
Introduction The endoplasmic reticulum (ER) stress-response, evoked in mice by the overexpression of class I major histocompatibility complex antigen (MHC-I), was proposed as a major mechanism responsible for skeletal muscle damage and dysfunction in autoimmune myositis. The present study was undertaken to characterize in more detail the ER stress-response occurring in myofibers of patients with inflammatory myopathies, focusing on the expression and distribution of Grp94, calreticulin and Grp75, three ER chaperones involved in immunomodulation. Methods Muscle biopsies were obtained from seven healthy subjects and 29 myositis patients, who were subdivided into groups based on the morphological evidence of inflammation and/or sarcolemmal immunoreactivity for MHC-I. Biopsies were analyzed by means of immunohistochemistry and western blot using anti-Grp94, anti-calreticulin and anti-Grp75 specific antibodies. Parallel analyses on these ER chaperones were conducted in rabbit and/or murine skeletal muscle after experimental induction of regeneration or systemic inflammation. Results Upregulation of Grp94 characterized regenerating myofibers of myositis patients (P = 0.03, compared with values detected in biopsies without signs of muscle regeneration) and developing and regenerating myofibers of mouse muscles. Conversely, levels of calreticulin and Grp75 increased about fourfold and twofold, respectively, in patient biopsies positive for sarcolemmal MHC-I immunoreactivity, compared with healthy subjects and patients negative for both inflammation and MHC-I labeling (P < 0.005). Differently from calreticulin, the Grp75 level increased significantly also in patient biopsies that displayed occasional sarcolemmal MHC-I immunoreactivity (P = 0.002), suggesting the interference of other mechanisms. Experimental systemic inflammation achieved in mice and rabbits by a single injection of bacterial lipopolysaccharide significantly increased Grp75 and calreticulin but not MHC-I expression in muscles. Conclusions These results indicate that, in myositis patients, muscle regeneration and inflammation, in addition to MHC-I upregulation, do evoke an ER stress-response characterized by the increased expression of Grp94 and Grp75, respectively. The increase in the muscle Grp75 level in patients showing occasional immunoreactivity for sarcolemmal MHC-I might be considered further as a broader indicator of idiopathic inflammatory myopathy.
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Affiliation(s)
- Maurizio Vitadello
- Institute of Neuroscience - Padova Section, Consiglio Nazionale delle Ricerche, viale G, Colombo 3, 35121 Padova, Italy
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Affiliation(s)
- Sandor Györke
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, USA.
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Lohan J, Culligan K, Ohlendieck K. Deficiency in Cardiac Dystrophin Affects the Abundance of the $\alpha$ -/ $\beta$ -Dystroglycan Complex. J Biomed Biotechnol 2005; 2005:28-36. [PMID: 15689636 PMCID: PMC1138265 DOI: 10.1155/jbb.2005.28] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Although Duchenne muscular dystrophy is primarily categorised as a skeletal muscle disease, deficiency in the membrane cytoskeletal protein dystrophin also affects the heart. The central transsarcolemmal linker between the actin membrane cytoskeleton and the extracellular matrix is represented by the dystrophin-associated dystroglycans. Chemical cross-linking analysis revealed no significant differences in the dimeric status of the $\alpha$ -/ $\beta$ -dystroglycan subcomplex in the dystrophic mdx heart as compared to normal cardiac tissue. In analogy to skeletal muscle fibres, heart muscle also exhibited a greatly reduced abundance of both dystroglycans in dystrophin-deficient cells. Immunoblotting demonstrated that the degree of reduction in $\alpha$ -dystroglycan is more pronounced in matured mdx skeletal muscle as contrasted to the mdx heart. The fact that the deficiency in dystrophin triggers a similar pathobiochemical response in both types of muscle suggests that the cardiomyopathic complications observed in $x$ -linked muscular dystrophy might be initiated by the loss of the dystrophin-associated surface glycoprotein complex.
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Affiliation(s)
- James Lohan
- Department of Biology, Faculty of Science, National University of Ireland, Maynooth, County
Kildare, Ireland
| | - Kevin Culligan
- Department of Biology, Faculty of Science, National University of Ireland, Maynooth, County
Kildare, Ireland
| | - Kay Ohlendieck
- Department of Biology, Faculty of Science, National University of Ireland, Maynooth, County
Kildare, Ireland
- *Kay Ohlendieck:
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Collet C, Ma J. Calcium-dependent facilitation and graded deactivation of store-operated calcium entry in fetal skeletal muscle. Biophys J 2005; 87:268-75. [PMID: 15240463 PMCID: PMC1304349 DOI: 10.1529/biophysj.103.039305] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Activation of store-operated Ca(2+) entry (SOCE) into the cytoplasm requires retrograde signaling from the intracellular Ca(2+) release machinery, a process that involves an intimate interaction between protein components on the intracellular and cell surface membranes. The cellular machinery that governs the Ca(2+) movement in muscle cells is developmentally regulated, reflecting maturation of the junctional membrane structure as well as coordinated expression of related Ca(2+) signaling molecules. Here we demonstrate the existence of SOCE in freshly isolated skeletal muscle cells obtained from embryonic days 15 and 16 of the mouse embryo, a critical stage of muscle development. SOCE in the fetal muscle deactivates incrementally with the uptake of Ca(2+) into the sarcoplasmic reticulum (SR). A novel Ca(2+)-dependent facilitation of SOCE is observed in cells transiently exposed to high cytosolic Ca(2+). Our data suggest that cytosolic Ca(2+) can facilitate SOCE whereas SR luminal Ca(2+) can deactivate SOCE in the fetal skeletal muscle. This cooperative mechanism of SOCE regulation by Ca(2+) ions not only enables tight control of SOCE by the SR membrane, but also provides an efficient mechanism of extracellular Ca(2+) entry in response to physiological demand. Such Ca(2+) signaling mechanism would likely contribute to contraction and development of the fetal skeletal muscle.
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Affiliation(s)
- Claude Collet
- Department of Physiology and Biophysics, The University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway, USA
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12
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Schertzer JD, Green HJ, Fowles JR, Duhamel TA, Tupling AR. Effects of prolonged exercise and recovery on sarcoplasmic reticulum Ca2+ cycling properties in rat muscle homogenates. ACTA ACUST UNITED AC 2004; 180:195-208. [PMID: 14738478 DOI: 10.1046/j.0001-6772.2003.01227.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To examine the effects of exercise and exercise plus active and passive recovery on sarcoplasmic reticulum (SR) Ca2+-handling properties. METHODS Crude muscle homogenates were prepared from adult rat gastrocnemius muscle from two experiments. In one experiment, the muscle was extracted immediately after prolonged treadmill running (RUN), after a 45 min period of reduced exercise intensity (RUN+) following RUN and compared with controls (CON). In the second experiment, muscle was extracted during passive recovery following the same run protocol at 10 min (REC10), 25 min (REC25) and 45 min (REC45) and compared with CON. RESULTS Sarcoplasmic reticulum Ca2+-uptake was 31% higher (P < 0.05) in RUN+ compared with CON and RUN. Higher values (P < 0.05) were also found in REC25 (48%) and REC45 (50%) compared with CON. Maximal Ca2+-ATPase was increased by 23% (P < 0.05) in RUN+ compared with CON and RUN and by 65-68% (P < 0.05) in REC25 and REC45 compared with CON. A higher (P < 0.05) Hill coefficient for Ca2+-ATPase activity was observed in RUN+ (2.3 +/- 0.2) compared with CON (1.7 +/- 0.2) or RUN (1.6 +/- 0.2), but not for any REC conditions. In addition, the coupling ratio (Ca2+-uptake/Ca2+-ATPase activity) was higher (P < 0.05) in RUN+ (2.2 +/- 0.10) compared with CON (1.9 +/- 0.05) and RUN (1.9 +/- 0.08). CONCLUSIONS It is concluded that in crude homogenates, SR Ca2+-uptake and Ca2+-ATPase activity are elevated in recovery following prolonged running and that the elevation in these properties is more pronounced during passive compared with active recovery.
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Affiliation(s)
- J D Schertzer
- Department of Kinesiology, University of Waterloo, Waterloo, Ontario, Canada
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Chevessier F, Marty I, Paturneau-Jouas M, Hantaï D, Verdière-Sahuqué M. Tubular aggregates are from whole sarcoplasmic reticulum origin: alterations in calcium binding protein expression in mouse skeletal muscle during aging. Neuromuscul Disord 2004; 14:208-16. [PMID: 15036331 DOI: 10.1016/j.nmd.2003.11.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2003] [Revised: 11/04/2003] [Accepted: 11/19/2003] [Indexed: 10/26/2022]
Abstract
Tubular aggregates are observed in various muscle disorders and appear as densely packed tubules believed to arise from sarcoplasmic reticulum of striated muscle. They are found both in human skeletal muscle, especially from patients suffering from 'tubular aggregate myopathy' and in fast twitch skeletal muscle of the male inbred mouse during aging. In this work, we studied tubular aggregates present in inbred male mouse skeletal muscle using electron microscopy as well as histochemistry and Western blotting with the main markers of the sarcoplasmic reticulum. We show that mouse tubular aggregates include the proteins SERCA 1, sarcalumenin (longitudinal sarcoplasmic reticulum), calsequestrin (terminal cisternae) and RyR1 (junctional sarcoplasmic reticulum). We demonstrate also that 95 and 51 kDa triadin isoforms are present in mouse skeletal muscle and are both components of tubular aggregates. These results support the hypothesis that tubular aggregates form a tubular arrangement of a complete sarcoplasmic reticulum containing the junctional, cisternae and longitudinal components of sarcoplasmic reticulum implicated in calcium homeostasis. During mouse skeletal muscle aging, however, densitometry of Western blots reveals a persistent decrease in the expression of the calcium binding protein calreticulin as well as a continuous increase in calsequestrin-like protein expression which both appear unrelated to the tubular aggregate formation.
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Affiliation(s)
- F Chevessier
- INSERM U582, Institut de Myologie, IFR 14, UPMC, Groupe Hospitalier Pitié-Salpêtrière, 47 Boulevard de l'Hôpital, 75651 Paris Cedex 13, France
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Biehn SE, Czymmek KJ, Leavens KF, Karin NJ. Expression of the sarco/endoplasmic Ca2+-ATPase, SERCA1a, in fibroblasts induces the formation of organelle membrane arrays. Exp Cell Res 2004; 292:78-88. [PMID: 14720508 DOI: 10.1016/j.yexcr.2003.08.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Members of the sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA) family are transmembrane proteins that are essential for the function of intracellular Ca(2+) storage organelles. We found that overexpression of avian muscle SERCA1a in transfected mouse fibroblasts led to the appearance of tubular membrane bundles that we termed plaques. These structures were generated in transfected cells when SERCA1a protein expression approached the endogenous level measured in chicken skeletal muscle. Plaque membranes had associated ribosomes and contained endoplasmic reticulum (ER) proteins. Endogenous ER protein levels were not elevated in SERCA1a-expressing cells, indicating that plaques were not generalized proliferations of ER but rather a reorganization of existing organelle membrane. Plaque formation also was observed in cells expressing a green fluorescent protein-SERCA1a fusion protein (GFP-SERCA1a). GFP-SERCA1a molecules displayed extensive lateral mobility between plaques, suggesting the presence of membrane continuities between these structures. Plaques were induced in cells expressing cDNA encoding a catalytically silent SERCA1a mutant indicating that ER redistribution was driven by a structural feature of the enzyme. SERCA1a-induced plaque formation shares some characteristics of sarcoplasmic reticulum (SR) biogenesis during muscle differentiation, and high-level SERCA1a expression in vivo may contribute to the formation of SR from ER during embryonic myogenesis.
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Affiliation(s)
- Suzanne E Biehn
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
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Glover L, Quinn S, Ryan M, Pette D, Ohlendieck K. Supramolecular calsequestrin complex. EUROPEAN JOURNAL OF BIOCHEMISTRY 2002; 269:4607-16. [PMID: 12230573 DOI: 10.1046/j.1432-1033.2002.03160.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
As recently demonstrated by overlay assays using calsequestrin-peroxidase conjugates, the major 63 kDa Ca(2+)-binding protein of the sarcoplasmic reticulum forms complexes with itself, and with junctin (26 kDa), triadin (94 kDa) and the ryanodine receptor (560 kDa) [Glover, L., Culligan, K., Cala, S., Mulvey, C. & Ohlendieck, K. (2001) Biochim. Biophys. Acta1515, 120-132]. Here, we show that variations in the relative abundance of these four central elements of excitation-contraction coupling in different fiber types, and during chronic electrostimulation-induced fiber type transitions, are reflected by distinct alterations in the calsequestrin overlay binding patterns. Comparative immunoblotting with antibodies to markers of the junctional sarcoplasmic reticulum, in combination with the calsequestrin overlay binding patterns, confirmed a lower ryanodine receptor expression in slow soleus muscle compared to fast fibers, and revealed a drastic reduction of the RyR1 isoform in chronic low-frequency stimulated tibialis anterior muscle. The fast-to-slow transition process included a distinct reduction in fast calsequestrin and triadin and a concomitant reduction in calsequestrin binding to these sarcoplasmic reticulum elements. The calsequestrin-binding protein junctin was not affected by the muscle transformation process. The increase in calsequestrin and decrease in junctin expression during postnatal development resulted in similar changes in the intensity of binding of the calsequestrin conjugate to these sarcoplasmic reticulum components. Aged skeletal muscle fibers tended towards reduced protein interactions within the calsequestrin complex. This agrees with the physiological concept that the key regulators of Ca(2+) homeostasis exist in a supramolecular membrane assembly and that protein-protein interactions are affected by isoform shifting underlying the finely tuned adaptation of muscle fibers to changed functional demands.
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Affiliation(s)
- Louise Glover
- Department of Pharmacology, University College Dublin, Belfield, Ireland
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Talon S, Vallot O, Huchet-Cadiou C, Lompré AM, Léoty C. IP(3)-induced tension and IP(3)-receptor expression in rat soleus muscle during postnatal development. Am J Physiol Regul Integr Comp Physiol 2002; 282:R1164-73. [PMID: 11893622 DOI: 10.1152/ajpregu.00073.2001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The present study was designed to examine whether changes in Ca(2+) release by inositol-1,4,5-trisphosphate (IP(3)) in 8-, 15-, and 30-day-old rat skeletal muscles could be associated with the expression of IP(3) receptors. Experiments were conducted in slow-twitch muscle in which both IP(3)-induced Ca(2+) release and IP(3)-receptor (IP(3)R) expression have been shown to be larger than in fast-twitch muscle. In saponin-skinned fibers, IP(3) induced transient contractile responses in which the amplitude was dependent on the Ca(2+)-loading period with the maximal IP(3) contracture being at 20 min of loading. The IP(3) tension decreased during postnatal development, was partially inhibited by ryanodine (100 microM), and was blocked by heparin (20-400 microg/ml). Amplification of the DNA sequence encoding for IP(3)R isoforms (using the RT-PCR technique) showed that in slow-twitch muscle, the type 2 isoform is mainly expressed, and its level decreases during postnatal development in parallel with changes in IP(3) responses in immature fibers. IP(3)-induced Ca(2+) release would then have greater participation in excitation-contraction coupling in developing fibers than in mature muscle.
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MESH Headings
- Age Factors
- Animals
- Anticoagulants/pharmacology
- Caffeine/pharmacology
- Calcium/metabolism
- Calcium Channels/genetics
- Calcium Channels/metabolism
- Detergents
- Gene Expression/physiology
- Heparin/pharmacology
- Inositol 1,4,5-Trisphosphate/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Muscle Contraction/drug effects
- Muscle Contraction/physiology
- Muscle Fibers, Slow-Twitch/metabolism
- Muscle, Skeletal/cytology
- Muscle, Skeletal/growth & development
- Muscle, Skeletal/metabolism
- Octoxynol
- Phosphodiesterase Inhibitors/pharmacology
- RNA, Messenger/analysis
- Rats
- Rats, Wistar
- Receptors, Cytoplasmic and Nuclear/genetics
- Receptors, Cytoplasmic and Nuclear/metabolism
- Ryanodine/pharmacology
- Ryanodine Receptor Calcium Release Channel/genetics
- Sarcoplasmic Reticulum/metabolism
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Affiliation(s)
- Sophie Talon
- Laboratoire de Physiologie Générale, Unité Mixte de Recherche 6018 du Centre National de la Recherche Scientifique, Faculté des Sciences et des Techniques, Université de Nantes, F-44322 Nantes, Cedex 03, France
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17
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Spangenburg EE, Lees SJ, Otis JS, Musch TI, Talmadge RJ, Williams JH. Effects of moderate heart failure and functional overload on rat plantaris muscle. J Appl Physiol (1985) 2002; 92:18-24. [PMID: 11744638 DOI: 10.1152/jappl.2002.92.1.18] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
It is thought that changes in sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) of skeletal muscle contribute to alterations in skeletal muscle function during congestive heart failure (CHF). It is well established that exercise training can improve muscle function. However, it is unclear whether similar adaptations will result from exercise training in a CHF patient. Therefore, the purpose of this study was to determine whether skeletal muscle during moderate CHF adapts to increased activity, utilizing the functional overload (FO) model. Significant increases in plantaris mass of the CHF-FO and sham-FO groups compared with the CHF and control (sham) groups were observed. Ca(2+) uptake rates were significantly elevated in the CHF group compared with all other groups. No differences were detected in Ca(2+) uptake rates between the CHF-FO, sham, and sham-FO groups. Increases in Ca(2+) uptake rates in moderate-CHF rats were not due to changes in SERCA isoform proportions; however, FO may have attenuated the CHF-induced increases through alterations in SERCA isoform expression. Therefore, changes in skeletal muscle Ca(2+) handling during moderate CHF may be due to alterations in regulatory mechanisms, which exercise may override, by possibly altering SERCA isoform expression.
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Affiliation(s)
- Espen E Spangenburg
- Muscular Function Laboratory, Department of Human Nutrition, Foods, and Exercise, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
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18
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Chapter 5 Hibernation: Protein adaptations. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s1568-1254(01)80007-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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19
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Harmon S, Froemming GR, Leisner E, Pette D, Ohlendieck K. Low-frequency stimulation of fast muscle affects the abundance of Ca(2+)-ATPase but not its oligomeric status. J Appl Physiol (1985) 2001; 90:371-9. [PMID: 11133930 DOI: 10.1152/jappl.2001.90.1.371] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
After chronic, low-frequency stimulation, a rapid decline in Ca(2+) pump activity is observed during the early stages of skeletal muscle transformation. However, this variation in enzymatic activity does not coincide with a drastic reduction in the amount of sarcoplasmic reticulum Ca(2+)-ATPases. To investigate whether changes in subunit interactions within Ca(2+) pump complexes contribute to this phenomena, we performed a chemical cross-linking analysis of 4 days continuously, and 4 days discontinuously, electrostimulated fast muscle fibers. The abundance of the slow and fast Ca(2+)-ATPase isoforms sarco(endo)plasmic reticulum Ca(2+)- ATPase types 1 and 2 was affected during the fast-to-slow transition process, demonstrating that, even after short-term stimulation, distinct changes in the isoform expression pattern of muscle proteins occur. However, the oligomeric status of both ion pump species did not change. Hence, chemical modifications of critical enzyme domains must be responsible for the rapid stimulation-induced activity changes, not variations in protein-protein interactions within Ca(2+)-ATPase units. Oligomerization appears to be of central importance to the proper physiological functioning of the Ca(2+)-ATPase and does not undergo changes during skeletal muscle conditioning.
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Affiliation(s)
- S Harmon
- Department of Pharmacology, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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20
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Ryan M, Carlson BM, Ohlendieck K. Oligomeric status of the dihydropyridine receptor in aged skeletal muscle. MOLECULAR CELL BIOLOGY RESEARCH COMMUNICATIONS : MCBRC 2000; 4:224-9. [PMID: 11409916 DOI: 10.1006/mcbr.2001.0282] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A prominent feature of aging is represented by a decrease in muscle mass and strength. Abnormalities in Ca2+ -regulatory membrane complexes are involved in many muscular disorders. In analogy, we determined potential age-related changes in a key component of excitation-contraction coupling, the dihydropyridine receptor. Immunoblotting of the microsomal fraction from aged rabbit muscle revealed a drastic decline in the voltage-sensing alpha1-subunit of this transverse-tubular receptor, but only marginally altered expression of its auxiliary alpha(2)-subunit and the Na+/K+ -ATPase. A shift to slower fibre type characteristics was indicated by an age-related increase in the slow calsequestrin isoform. Chemical crosslinking analysis showed that the triad receptor complex has a comparable tendency of protein-protein interactions in young and aged muscles. Hence, a reduced expression and not modified oligomerization of the principal dihydropyridine receptor subunit might be involved in triggering impaired triadic signal transduction and abnormal Ca2+ -homeostasis resulting in a progressive functional decline of skeletal muscles.
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Affiliation(s)
- M Ryan
- Department of Pharmacology, University College Dublin, Dublin, Belfield, 4, Ireland
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21
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Berchtold MW, Brinkmeier H, Müntener M. Calcium ion in skeletal muscle: its crucial role for muscle function, plasticity, and disease. Physiol Rev 2000; 80:1215-65. [PMID: 10893434 DOI: 10.1152/physrev.2000.80.3.1215] [Citation(s) in RCA: 609] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mammalian skeletal muscle shows an enormous variability in its functional features such as rate of force production, resistance to fatigue, and energy metabolism, with a wide spectrum from slow aerobic to fast anaerobic physiology. In addition, skeletal muscle exhibits high plasticity that is based on the potential of the muscle fibers to undergo changes of their cytoarchitecture and composition of specific muscle protein isoforms. Adaptive changes of the muscle fibers occur in response to a variety of stimuli such as, e.g., growth and differentition factors, hormones, nerve signals, or exercise. Additionally, the muscle fibers are arranged in compartments that often function as largely independent muscular subunits. All muscle fibers use Ca(2+) as their main regulatory and signaling molecule. Therefore, contractile properties of muscle fibers are dependent on the variable expression of proteins involved in Ca(2+) signaling and handling. Molecular diversity of the main proteins in the Ca(2+) signaling apparatus (the calcium cycle) largely determines the contraction and relaxation properties of a muscle fiber. The Ca(2+) signaling apparatus includes 1) the ryanodine receptor that is the sarcoplasmic reticulum Ca(2+) release channel, 2) the troponin protein complex that mediates the Ca(2+) effect to the myofibrillar structures leading to contraction, 3) the Ca(2+) pump responsible for Ca(2+) reuptake into the sarcoplasmic reticulum, and 4) calsequestrin, the Ca(2+) storage protein in the sarcoplasmic reticulum. In addition, a multitude of Ca(2+)-binding proteins is present in muscle tissue including parvalbumin, calmodulin, S100 proteins, annexins, sorcin, myosin light chains, beta-actinin, calcineurin, and calpain. These Ca(2+)-binding proteins may either exert an important role in Ca(2+)-triggered muscle contraction under certain conditions or modulate other muscle activities such as protein metabolism, differentiation, and growth. Recently, several Ca(2+) signaling and handling molecules have been shown to be altered in muscle diseases. Functional alterations of Ca(2+) handling seem to be responsible for the pathophysiological conditions seen in dystrophinopathies, Brody's disease, and malignant hyperthermia. These also underline the importance of the affected molecules for correct muscle performance.
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Affiliation(s)
- M W Berchtold
- Department of Molecular Cell Biology, Institute of Molecular Biology, University of Copenhagen, Copenhagen, Denmark.
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Froemming GR, Murray BE, Harmon S, Pette D, Ohlendieck K. Comparative analysis of the isoform expression pattern of Ca(2+)-regulatory membrane proteins in fast-twitch, slow-twitch, cardiac, neonatal and chronic low-frequency stimulated muscle fibers. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1466:151-68. [PMID: 10825439 DOI: 10.1016/s0005-2736(00)00195-4] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although all muscle cells generate contractile forces by means of organized filament systems, isoform expression patterns of contractile and regulatory proteins in heart are not identical compared to developing, conditioned or mature skeletal muscles. In order to determine biochemical parameters that may reflect functional variations in the Ca(2+)-regulatory membrane systems of different muscle types, we performed a comparative immunoblot analysis of key membrane proteins involved in ion homeostasis. Cardiac isoforms of the alpha(1)-dihydropyridine receptor, Ca(2+)-ATPase and calsequestrin are also present in skeletal muscle and are up-regulated in chronic low-frequency stimulated fast muscle. In contrast, the cardiac RyR2 isoform of the Ca(2+)-release channel was not found in slow muscle but was detectable in neonatal skeletal muscle. Up-regulation of RyR2 in conditioned muscle was probably due to degeneration-regeneration processes. Fiber type-specific differences were also detected in the abundance of auxiliary subunits of the dihydropyridine receptor, the ryanodine receptor and the Ca(2+)-ATPase, as well as triad markers and various Ca(2+)-binding and ion-regulatory proteins. Hence, the variation in innervation of different types of muscle appears to have a profound influence on the levels and pattern of isoform expression of Ca(2+)-regulatory membrane proteins reflecting differences in the regulation of Ca(2+)-homeostasis. However, independent of the muscle cell type, key Ca(2+)-regulatory proteins exist as oligomeric complexes under native conditions.
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Affiliation(s)
- G R Froemming
- Department of Pharmacology, Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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Froemming GR, Pette D, Ohlendieck K. The 90-kDa junctional sarcoplasmic reticulum protein forms an integral part of a supramolecular triad complex in skeletal muscle. Biochem Biophys Res Commun 1999; 261:603-9. [PMID: 10441473 DOI: 10.1006/bbrc.1999.1032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although it is well established that voltage-sensing of the alpha(1)-dihydropyridine receptor triggers Ca(2+)-release via the ryanodine receptor during excitation-contraction coupling in skeletal muscle fibers, it remains to be determined which junctional components are responsible for the assembly, maintenance, and stabilization of triads. Here, we analyzed the expression pattern and neighborhood relationship of a novel 90-kDa sarcoplasmic reticulum protein. This protein is highly enriched in the triad fraction and is predominantly expressed in fast-twitching muscle fibers. Chronic low-frequency electro-stimulation induced a drastic decrease in the relative abundance of this protein. Chemical crosslinking showed a potential overlap between the 90-kDa junctional face membrane protein and the ryanodine receptor Ca(2+)-release channel, suggesting tight protein-protein interactions between these two triad components. Hence, Ca(2+)-regulatory muscle proteins have a strong tendency to oligomerize and the triad region of skeletal muscle fibers forms supramolecular membrane complexes involved in the regulation of Ca(2+)-homeostasis and signal transduction.
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Affiliation(s)
- G R Froemming
- National University of Ireland, University College Dublin, Belfield, Dublin, 4, Ireland
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Lennon NJ, Harmon S, Mackey A, Ohlendieck K. Oligomerization of the sarcoplasmic reticulum Ca2+-ATPase SERCA2 in cardiac muscle. MOLECULAR CELL BIOLOGY RESEARCH COMMUNICATIONS : MCBRC 1999; 1:182-7. [PMID: 10425224 DOI: 10.1006/mcbr.1999.0129] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The slow/cardiac isoform of the sarcoplasmic reticulum Ca2+-ATPase plays an important role in cardiac muscle Ca2+-homeostasis. To determine the native configuration of the SERCA2 ion pump, a chemical cross-linking analysis of heart microsomes was performed. Using one- and two-dimensional immunoblotting following incubation with the hydrophilic probe bis-sulfosuccinimidyl suberate or the hydrophobic crosslinker dithiobis-succinimidyl-propionate, we demonstrate here that SERCA2 forms high-molecular-mass aggregates. In contrast to the Na+/Ca2+-exchanger, Ca2+-ATPase clusters can be stabilized by hydrophilic 1.2 nm crosslinkers and are sensitive to chemical reduction. Hence, the native form of this important Ca2+-regulatory membrane protein involved in cardiac muscle relaxation appears not to exist as a monomeric ion pump unit. Protein-protein interactions might play an important role in the physiological functioning of this Ca2+-ATPase isoform, as has previously been shown for skeletal muscle Ca2+-pumps, Ca2+-binding proteins and Ca2+-channels.
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Affiliation(s)
- N J Lennon
- Department of Pharmacology, National University of Ireland, University College Dublin, Belfield
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Froemming GR, Murray BE, Ohlendieck K. Self-aggregation of triadin in the sarcoplasmic reticulum of rabbit skeletal muscle. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1418:197-205. [PMID: 10209224 DOI: 10.1016/s0005-2736(99)00024-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The 95 kDa transmembrane glycoprotein triadin is believed to be an essential component of excitation-contraction coupling in the junctional sarcoplasmic reticulum of skeletal muscle fibers. It is debatable whether triadin mediates intraluminal interactions between calsequestrin and the ryanodine receptor exclusively or whether this junctional protein provides also a cytoplasmic linkage between the Ca2+-release channel and the dihydropyridine receptor. Here, we could show that native triadin exists as disulfide-linked homo-polymers of above 3000 kDa. Under non-reducing conditions, protein bands representing the alpha1-dihydropyridine receptor and calsequestrin did not show an immunodecorative overlap with the extremely high-molecular-mass triadin clusters. Following chemical crosslinking, the ryanodine receptor and triadin exhibited a similarly decreased electrophoretic mobility. However, immunoblotting of diagonal non-reducing/reducing two-dimensional gels clearly demonstrated a lack of overlap between the immunodecorated bands representing triadin, the alpha1-dihydropyridine receptor, the ryanodine receptor and calsequestrin. Thus, in native membranes triadin appears to form large self-aggregates primarily. Although triadin exists in a close neighborhood relationship to the Ca2+-release channel tetramers, it does not seem to be directly linked to the other main triad components implicated in the regulation of the excitation-contraction-relaxation cycle and Ca2+-homeostasis. This agrees with a proposed role of triadin in the maintenance of overall triad architecture.
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Affiliation(s)
- G R Froemming
- Department of Pharmacology, National University of Ireland, University College Dublin, Belfield, Dublin 4, Ireland
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