1
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Poudel BH, Fletcher S, Wilton SD, Aung-Htut M. Limb Girdle Muscular Dystrophy Type 2B (LGMD2B): Diagnosis and Therapeutic Possibilities. Int J Mol Sci 2024; 25:5572. [PMID: 38891760 PMCID: PMC11171558 DOI: 10.3390/ijms25115572] [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: 04/18/2024] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 06/21/2024] Open
Abstract
Dysferlin is a large transmembrane protein involved in critical cellular processes including membrane repair and vesicle fusion. Mutations in the dysferlin gene (DYSF) can result in rare forms of muscular dystrophy; Miyoshi myopathy; limb girdle muscular dystrophy type 2B (LGMD2B); and distal myopathy. These conditions are collectively known as dysferlinopathies and are caused by more than 600 mutations that have been identified across the DYSF gene to date. In this review, we discuss the key molecular and clinical features of LGMD2B, the causative gene DYSF, and the associated dysferlin protein structure. We also provide an update on current approaches to LGMD2B diagnosis and advances in drug development, including splice switching antisense oligonucleotides. We give a brief update on clinical trials involving adeno-associated viral gene therapy and the current progress on CRISPR/Cas9 mediated therapy for LGMD2B, and then conclude by discussing the prospects of antisense oligomer-based intervention to treat selected mutations causing dysferlinopathies.
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Affiliation(s)
- Bal Hari Poudel
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA 6150, Australia; (B.H.P.); (S.F.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA 6009, Australia
- Central Department of Biotechnology, Tribhuvan University, Kirtipur, Kathmandu 44618, Nepal
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA 6150, Australia; (B.H.P.); (S.F.); (S.D.W.)
| | - Steve D. Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA 6150, Australia; (B.H.P.); (S.F.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA 6009, Australia
| | - May Aung-Htut
- Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute, Murdoch University, Perth, WA 6150, Australia; (B.H.P.); (S.F.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, The University of Western Australia, Perth, WA 6009, Australia
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2
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Bouchard C, Tremblay JP. Portrait of Dysferlinopathy: Diagnosis and Development of Therapy. J Clin Med 2023; 12:6011. [PMID: 37762951 PMCID: PMC10531777 DOI: 10.3390/jcm12186011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023] Open
Abstract
Dysferlinopathy is a disease caused by a dysferlin deficiency due to mutations in the DYSF gene. Dysferlin is a membrane protein in the sarcolemma and is involved in different functions, such as membrane repair and vesicle fusion, T-tubule development and maintenance, Ca2+ signalling, and the regulation of various molecules. Miyoshi Myopathy type 1 (MMD1) and Limb-Girdle Muscular Dystrophy 2B/R2 (LGMD2B/LGMDR2) are two possible clinical presentations, yet the same mutations can cause both presentations in the same family. They are therefore grouped under the name dysferlinopathy. Onset is typically during the teenage years or young adulthood and is characterized by a loss of Achilles tendon reflexes and difficulty in standing on tiptoes or climbing stairs, followed by a slow progressive loss of strength in limb muscles. The MRI pattern of patient muscles and their biopsies show various fibre sizes, necrotic and regenerative fibres, and fat and connective tissue accumulation. Recent tools were developed for diagnosis and research, especially to evaluate the evolution of the patient condition and to prevent misdiagnosis caused by similarities with polymyositis and Charcot-Marie-Tooth disease. The specific characteristic of dysferlinopathy is dysferlin deficiency. Recently, mouse models with patient mutations were developed to study genetic approaches to treat dysferlinopathy. The research fields for dysferlinopathy therapy include symptomatic treatments, as well as antisense-mediated exon skipping, myoblast transplantation, and gene editing.
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Affiliation(s)
- Camille Bouchard
- Département de Médecine Moléculaire, Université Laval, Québec, QC G1V 0A6, Canada;
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1E 6W2, Canada
| | - Jacques P. Tremblay
- Département de Médecine Moléculaire, Université Laval, Québec, QC G1V 0A6, Canada;
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Québec, QC G1E 6W2, Canada
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3
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Kwok E, Otto SC, Khuu P, Carpenter AP, Codding SJ, Reardon PN, Vanegas J, Kumar TM, Kuykendall CJ, Mehl RA, Baio J, Johnson CP. The Dysferlin C2A Domain Binds PI(4,5)P2 and Penetrates Membranes. J Mol Biol 2023; 435:168193. [PMID: 37406927 PMCID: PMC10699586 DOI: 10.1016/j.jmb.2023.168193] [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: 02/06/2023] [Revised: 06/22/2023] [Accepted: 06/27/2023] [Indexed: 07/07/2023]
Abstract
Dysferlin is a large membrane protein found most prominently in striated muscle. Loss of dysferlin activity is associated with reduced exocytosis, abnormal intracellular Ca2+ and the muscle diseases limb-girdle muscular dystrophy and Miyoshi myopathy. The cytosolic region of dysferlin consists of seven C2 domains with mutations in the C2A domain at the N-terminus resulting in pathology. Despite the importance of Ca2+ and membrane binding activities of the C2A domain for dysferlin function, the mechanism of the domain remains poorly characterized. In this study we find that the C2A domain preferentially binds membranes containing PI(4,5)P2 through an interaction mediated by residues Y23, K32, K33, and R77 on the concave face of the domain. We also found that subsequent to membrane binding, the C2A domain inserts residues on the Ca2+ binding loops into the membrane. Analysis of solution NMR measurements indicate that the domain inhabits two distinct structural states, with Ca2+ shifting the population between states towards a more rigid structure with greater affinity for PI(4,5)P2. Based on our results, we propose a mechanism where Ca2+ converts C2A from a structurally dynamic, low PI(4,5)P2 affinity state to a high affinity state that targets dysferlin to PI(4,5)P2 enriched membranes through interaction with Tyr23, K32, K33, and R77. Binding also involves changes in lipid packing and insertion by the third Ca2+ binding loop of the C2 domain into the membrane, which would contribute to dysferlin function in exocytosis and Ca2+ regulation.
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Affiliation(s)
- Ethiene Kwok
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Shauna C Otto
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Patricia Khuu
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Andrew P Carpenter
- Department of Chemical Engineering, Oregon State University, Corvallis, OR 97331, USA
| | - Sara J Codding
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | | | - Juan Vanegas
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Tanushri M Kumar
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Chapman J Kuykendall
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Ryan A Mehl
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA
| | - Joe Baio
- Department of Chemical Engineering, Oregon State University, Corvallis, OR 97331, USA
| | - Colin P Johnson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97331, USA.
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4
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Naneh O, Kozorog M, Merzel F, Gilbert R, Anderluh G. Surface plasmon resonance and microscale thermophoresis approaches for determining the affinity of perforin for calcium ions. Front Immunol 2023; 14:1181020. [PMID: 37545534 PMCID: PMC10400287 DOI: 10.3389/fimmu.2023.1181020] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/16/2023] [Indexed: 08/08/2023] Open
Abstract
Perforin is a pore-forming protein that plays a crucial role in the immune system by clearing virus-infected or tumor cells. It is released from cytotoxic granules of immune cells and forms pores in targeted lipid membranes to deliver apoptosis-inducing granzymes. It is a very cytotoxic protein and is therefore adapted not to act in producing cells. Its activity is regulated by the requirement for calcium ions for optimal activity. However, the exact affinity of perforin for calcium ions has not yet been determined. We conducted a molecular dynamics simulation in the absence or presence of calcium ions that showed that binding of at least three calcium ions is required for stable perforin binding to the lipid membrane. Biophysical studies using surface plasmon resonance and microscale thermophoresis were then performed to estimate the binding affinities of native human and recombinant mouse perforin for calcium ions. Both approaches showed that mouse perforin has a several fold higher affinity for calcium ions than that of human perforin. This was attributed to a particular residue, tryptophan at position 488 in mouse perforin, which is replaced by arginine in human perforin. This represents an additional mechanism to control the activity of human perforin.
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Affiliation(s)
- Omar Naneh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Mirijam Kozorog
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
| | - Franci Merzel
- Theory Department, National Institute of Chemistry, Ljubljana, Slovenia
| | - Robert Gilbert
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Gregor Anderluh
- Department of Molecular Biology and Nanobiotechnology, National Institute of Chemistry, Ljubljana, Slovenia
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5
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Scott IL, Dominguez MJ, Snow A, Harsini FM, Williams J, Fuson KL, Thapa R, Bhattacharjee P, Cornwall GA, Keyel PA, Sutton RB. Pathogenic Mutations in the C2A Domain of Dysferlin form Amyloid that Activates the Inflammasome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.24.538129. [PMID: 37163031 PMCID: PMC10168229 DOI: 10.1101/2023.04.24.538129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Limb-Girdle Muscular Dystrophy Type-2B/2R is caused by mutations in the dysferlin gene ( DYSF ). This disease has two known pathogenic missense mutations that occur within dysferlin's C2A domain, namely C2A W52R and C2A V67D . Yet, the etiological rationale to explain the disease linkage for these two mutations is still unclear. In this study, we have presented evidence from biophysical, computational, and immunological experiments which suggest that these missense mutations interfere with dysferlin's ability to repair cells. The failure of C2A W52R and C2A V67D to initiate membrane repair arises from their propensity to form stable amyloid. The misfolding of the C2A domain caused by either mutation exposes β-strands, which are predicted to nucleate classical amyloid structures. When dysferlin C2A amyloid is formed, it triggers the NLRP3 inflammasome, leading to the secretion of inflammatory cytokines, including IL-1β. The present study suggests that the muscle dysfunction and inflammation evident in Limb-Girdle Muscular Dystrophy types-2B/2R, specifically in cases involving C2A W52R and C2A V67D , as well as other C2 domain mutations with considerable hydrophobic core involvement, may be attributed to this mechanism.
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6
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Role of calcium-sensor proteins in cell membrane repair. Biosci Rep 2023; 43:232522. [PMID: 36728029 PMCID: PMC9970828 DOI: 10.1042/bsr20220765] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 01/20/2023] [Accepted: 02/01/2023] [Indexed: 02/03/2023] Open
Abstract
Cell membrane repair is a critical process used to maintain cell integrity and survival from potentially lethal chemical, and mechanical membrane injury. Rapid increases in local calcium levels due to a membrane rupture have been widely accepted as a trigger for multiple membrane-resealing models that utilize exocytosis, endocytosis, patching, and shedding mechanisms. Calcium-sensor proteins, such as synaptotagmins (Syt), dysferlin, S100 proteins, and annexins, have all been identified to regulate, or participate in, multiple modes of membrane repair. Dysfunction of membrane repair from inefficiencies or genetic alterations in these proteins contributes to diseases such as muscular dystrophy (MD) and heart disease. The present review covers the role of some of the key calcium-sensor proteins and their involvement in membrane repair.
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7
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Carpenter AP, Khuu P, Weidner T, Johnson CP, Roeters SJ, Baio JE. Orientation of the Dysferlin C2A Domain is Responsive to the Composition of Lipid Membranes. J Phys Chem B 2023; 127:577-589. [PMID: 36608331 DOI: 10.1021/acs.jpcb.2c06716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dysferlin is a 230 kD protein that plays a critical function in the active resealing of micron-sized injuries to the muscle sarcolemma by recruiting vesicles to patch the injured site via vesicle fusion. Muscular dystrophy is observed in humans when mutations disrupt this repair process or dysferlin is absent. While lipid binding by dysferlin's C2A domain (dysC2A) is considered fundamental to the membrane resealing process, the molecular mechanism of this interaction is not fully understood. By applying nonlinear surface-specific vibrational spectroscopy, we have successfully demonstrated that dysferlin's N-terminal C2A domain (dysC2A) alters its binding orientation in response to a membrane's lipid composition. These experiments reveal that dysC2A utilizes a generic electrostatic binding interaction to bind to most anionic lipid surfaces, inserting its calcium binding loops into the lipid surface while orienting its β-sheets 30-40° from surface normal. However, at lipid surfaces, where PI(4,5)P2 is present, dysC2A tilts its β-sheets more than 60° from surface normal to expose a polybasic face, while it binds to the PI(4,5)P2 surface. Both lipid binding mechanisms are shown to occur alongside dysC2A-induced lipid clustering. These different binding mechanisms suggest that dysC2A could provide a molecular cue to the larger dysferlin protein as to signal whether it is bound to the sarcolemma or another lipid surface.
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Affiliation(s)
- Andrew P Carpenter
- The School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon97331, United States
| | - Patricia Khuu
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon97331, United States
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, 8000Aarhus C, Denmark
| | - Colin P Johnson
- Department of Biochemistry and Biophysics, Oregon State University, Corvallis, Oregon97331, United States
| | - Steven J Roeters
- Department of Chemistry, Aarhus University, 8000Aarhus C, Denmark
| | - Joe E Baio
- The School of Chemical, Biological, and Environmental Engineering, Oregon State University, Corvallis, Oregon97331, United States
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8
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Lukyanenko V, Muriel J, Garman D, Breydo L, Bloch RJ. Elevated Ca2+ at the triad junction underlies dysregulation of Ca2+ signaling in dysferlin-null skeletal muscle. Front Physiol 2022; 13:1032447. [PMID: 36406982 PMCID: PMC9669649 DOI: 10.3389/fphys.2022.1032447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 10/14/2022] [Indexed: 11/05/2022] Open
Abstract
Dysferlin-null A/J myofibers generate abnormal Ca2+ transients that are slightly reduced in amplitude compared to controls. These are further reduced in amplitude by hypoosmotic shock and often appear as Ca2+ waves (Lukyanenko et al., J. Physiol., 2017). Ca2+ waves are typically associated with Ca2+-induced Ca2+ release, or CICR, which can be myopathic. We tested the ability of a permeable Ca2+ chelator, BAPTA-AM, to inhibit CICR in injured dysferlin-null fibers and found that 10–50 nM BAPTA-AM suppressed all Ca2+ waves. The same concentrations of BAPTA-AM increased the amplitude of the Ca2+ transient in A/J fibers to wild type levels and protected transients against the loss of amplitude after hypoosmotic shock, as also seen in wild type fibers. Incubation with 10 nM BAPTA-AM led to intracellular BAPTA concentrations of ∼60 nM, as estimated with its fluorescent analog, Fluo-4AM. This should be sufficient to restore intracellular Ca2+ to levels seen in wild type muscle. Fluo-4AM was ∼10-fold less effective than BAPTA-AM, however, consistent with its lower affinity for Ca2+. EGTA, which has an affinity for Ca2+ similar to BAPTA, but with much slower kinetics of binding, was even less potent when introduced as the -AM derivative. By contrast, a dysferlin variant with GCaMP6fu in place of its C2A domain accumulated at triad junctions, like wild type dysferlin, and suppressed all abnormal Ca2+ signaling. GCaMP6fu introduced as a Venus chimera did not accumulate at junctions and failed to suppress abnormal Ca2+ signaling. Our results suggest that leak of Ca2+ into the triad junctional cleft underlies dysregulation of Ca2+ signaling in dysferlin-null myofibers, and that dysferlin’s C2A domain suppresses abnormal Ca2+ signaling and protects muscle against injury by binding Ca2+ in the cleft.
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Affiliation(s)
- Valeriy Lukyanenko
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Joaquin Muriel
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Daniel Garman
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States
- Program in Biochemistry and Molecular Biology, University of Maryland, Baltimore, MD, United States
| | - Leonid Breydo
- Formulation Development, Regeneron Pharmaceuticals, Tarrytown, NY, United States
| | - Robert J. Bloch
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States
- *Correspondence: Robert J. Bloch,
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9
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Dominguez MJ, McCord JJ, Sutton RB. Redefining the architecture of ferlin proteins: Insights into multi-domain protein structure and function. PLoS One 2022; 17:e0270188. [PMID: 35901179 PMCID: PMC9333456 DOI: 10.1371/journal.pone.0270188] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 06/07/2022] [Indexed: 11/18/2022] Open
Abstract
Ferlins are complex, multi-domain proteins, involved in membrane trafficking, membrane repair, and exocytosis. The large size of ferlin proteins and the lack of consensus regarding domain boundaries have slowed progress in understanding molecular-level details of ferlin protein structure and function. However, in silico protein folding techniques have significantly enhanced our understanding of the complex ferlin family domain structure. We used RoseTTAFold to assemble full-length models for the six human ferlin proteins (dysferlin, myoferlin, otoferlin, Fer1L4, Fer1L5, and Fer1L6). Our full-length ferlin models were used to obtain objective domain boundaries, and these boundaries were supported by AlphaFold2 predictions. Despite the differences in amino acid sequence between the ferlin proteins, the domain ranges and distinct subdomains in the ferlin domains are remarkably consistent. Further, the RoseTTAFold/AlphaFold2 in silico boundary predictions allowed us to describe and characterize a previously unknown C2 domain, ubiquitous in all human ferlins, which we refer to as C2-FerA. At present, the ferlin domain-domain interactions implied by the full-length in silico models are predicted to have a low accuracy; however, the use of RoseTTAFold and AlphaFold2 as a domain finder has proven to be a powerful research tool for understanding ferlin structure.
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Affiliation(s)
- Matthew J. Dominguez
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
| | - Jon J. McCord
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
| | - R. Bryan Sutton
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, United States of America
- * E-mail:
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10
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Muriel J, Lukyanenko V, Kwiatkowski T, Bhattacharya S, Garman D, Weisleder N, Bloch RJ. The C2 domains of dysferlin: Roles in membrane localization, Ca
2+
signaling and sarcolemmal repair. J Physiol 2022; 600:1953-1968. [PMID: 35156706 PMCID: PMC9285653 DOI: 10.1113/jp282648] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 02/03/2022] [Indexed: 11/08/2022] Open
Abstract
Dysferlin is an integral membrane protein of the transverse tubules of skeletal muscle that is mutated or absent in limb girdle muscular dystrophy 2B and Miyoshi myopathy. Here we examine the role of dysferlin's seven C2 domains, C2A through C2G, in membrane repair and Ca2+ release, as well as in targeting dysferlin to the transverse tubules of skeletal muscle. We report that deletion of either domain C2A or C2B inhibits membrane repair completely, whereas deletion of C2C, C2D, C2E, C2F or C2G causes partial loss of membrane repair that is exacerbated in the absence of extracellular Ca2+ . Deletion of C2C, C2D, C2E, C2F or C2G also causes significant changes in Ca2+ release, measured as the amplitude of the Ca2+ transient before or after hypo-osmotic shock and the appearance of Ca2+ waves. Most deletants accumulate in endoplasmic reticulum. Only the C2A domain can be deleted without affecting dysferlin trafficking to transverse tubules, but Dysf-ΔC2A fails to support normal Ca2+ signalling after hypo-osmotic shock. Our data suggest that (i) every C2 domain contributes to repair; (ii) all C2 domains except C2B regulate Ca2+ signalling; (iii) transverse tubule localization is insufficient for normal Ca2+ signalling; and (iv) Ca2+ dependence of repair is mediated by C2C through C2G. Thus, dysferlin's C2 domains have distinct functions in Ca2+ signalling and sarcolemmal membrane repair and may play distinct roles in skeletal muscle. KEY POINTS: Dysferlin, a transmembrane protein containing seven C2 domains, C2A through C2G, concentrates in transverse tubules of skeletal muscle, where it stabilizes voltage-induced Ca2+ transients and participates in sarcolemmal membrane repair. Each of dysferlin's C2 domains except C2B regulate Ca2+ signalling. Localization of dysferlin variants to the transverse tubules is not sufficient to support normal Ca2+ signalling or membrane repair. Each of dysferlin's C2 domains contributes to sarcolemmal membrane repair. The Ca2+ dependence of membrane repair is mediated by C2C through C2G. Dysferlin's C2 domains therefore have distinct functions in Ca2+ signalling and sarcolemmal membrane repair.
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Affiliation(s)
- Joaquin Muriel
- Department of Physiology University of Maryland School of Medicine Baltimore MD 21208
| | - Valeriy Lukyanenko
- Department of Physiology University of Maryland School of Medicine Baltimore MD 21208
| | - Tom Kwiatkowski
- Department of Physiology The Ohio State College of Medicine Columbus OH 43210
| | - Sayak Bhattacharya
- Department of Physiology The Ohio State College of Medicine Columbus OH 43210
| | - Daniel Garman
- Department of Physiology University of Maryland School of Medicine Baltimore MD 21208
| | - Noah Weisleder
- Department of Physiology The Ohio State College of Medicine Columbus OH 43210
| | - Robert J. Bloch
- Department of Physiology University of Maryland School of Medicine Baltimore MD 21208
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11
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Diercks BP, Jensen HH, Chalmers SB, Coode E, Vaughan MB, Tadayon R, Sáez PJ, Davis FM, Brohus M. The first junior European Calcium Society meeting: calcium research across scales, Kingdoms and countries. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:118999. [PMID: 33711364 DOI: 10.1016/j.bbamcr.2021.118999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/05/2021] [Accepted: 02/20/2021] [Indexed: 01/09/2023]
Abstract
The first junior European Calcium Society online meeting, held October 20-21, 2020, aimed to promote junior researchers in the Ca2+ community. The meeting included four scientific sessions, covering Ca2+ research from molecular detail to whole organisms. Each session featured one invited speaker and three speakers selected based on submitted abstracts, with the overall aim of actively involving early-career researchers. Consequently, the meeting underlined the diversity of Ca2+ physiology, by showcasing research across scales and Kingdoms, as presented by a correspondingly diverse speaker panel across career stages and countries. In this meeting report, we introduce the visions of the junior European Calcium Society board and summarize the meeting content.
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Affiliation(s)
- Björn-Philipp Diercks
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg - Eppendorf, Hamburg, Germany.
| | - Helene H Jensen
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
| | - Silke B Chalmers
- School of Pharmacy, The University of Queensland, Brisbane, Queensland, Australia
| | - Emily Coode
- School of Life, Health and Chemical Sciences, The Open University, Walton Hall, Milton Keynes, UK
| | - Michael B Vaughan
- Department of Physiology, School of Medicine, University College Cork, Cork, Ireland
| | - Roya Tadayon
- Department of Biochemistry, School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Pablo J Sáez
- Department of Biochemistry and Molecular Cell Biology, University Medical Center Hamburg - Eppendorf, Hamburg, Germany
| | - Felicity M Davis
- EMBL Australia Node for Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Malene Brohus
- Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark.
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