1
|
Sert O, Ding X, Zhang C, Mi R, Hoke A, Rasband MN. Postsynaptic β1 spectrin maintains Na + channels at the neuromuscular junction. J Physiol 2024; 602:1127-1145. [PMID: 38441922 PMCID: PMC10942750 DOI: 10.1113/jp285894] [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: 11/01/2023] [Accepted: 02/13/2024] [Indexed: 03/16/2024] Open
Abstract
Spectrins function together with actin as obligatory subunits of the submembranous cytoskeleton. Spectrins maintain cell shape, resist mechanical forces, and stabilize ion channel and transporter protein complexes through binding to scaffolding proteins. Recently, pathogenic variants of SPTBN4 (β4 spectrin) were reported to cause both neuropathy and myopathy. Although the role of β4 spectrin in neurons is mostly understood, its function in skeletal muscle, another excitable tissue subject to large forces, is unknown. Here, using a muscle specific β4 spectrin conditional knockout mouse, we show that β4 spectrin does not contribute to muscle function. In addition, we show β4 spectrin is not present in muscle, indicating the previously reported myopathy associated with pathogenic SPTBN4 variants is neurogenic in origin. More broadly, we show that α2, β1 and β2 spectrins are found in skeletal muscle, with α2 and β1 spectrins being enriched at the postsynaptic neuromuscular junction (NMJ). Surprisingly, using muscle specific conditional knockout mice, we show that loss of α2 and β2 spectrins had no effect on muscle health, function or the enrichment of β1 spectrin at the NMJ. Muscle specific deletion of β1 spectrin also had no effect on muscle health, but, with increasing age, resulted in the loss of clustered NMJ Na+ channels. Together, our results suggest that muscle β1 spectrin functions independently of an associated α spectrin to maintain Na+ channel clustering at the postsynaptic NMJ. Furthermore, despite repeated exposure to strong forces and in contrast to neurons, muscles do not require spectrin cytoskeletons to maintain cell shape or integrity. KEY POINTS: The myopathy found in pathogenic human SPTBN4 variants (where SPTBN4 is the gene encoding β4 spectrin) is neurogenic in origin. β1 spectrin plays essential roles in maintaining the density of neuromuscular junction Nav1.4 Na+ channels. By contrast to the canonical view of spectrin organization and function, we show that β1 spectrin can function independently of an associated α spectrin. Despite the large mechanical forces experienced by muscle, we show that spectrins are not required for muscle cell integrity. This is in stark contrast to red blood cells and the axons of neurons.
Collapse
Affiliation(s)
- Ozlem Sert
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA 77030
| | - Xiaoyun Ding
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA 77030
| | - Chuansheng Zhang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA 77030
| | - Ruifa Mi
- Departments of Neurology and Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD 21205
| | - Ahmet Hoke
- Departments of Neurology and Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD 21205
| | - Matthew N. Rasband
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA 77030
| |
Collapse
|
2
|
Weiss N, Zamponi GW. The T-type calcium channelosome. Pflugers Arch 2024; 476:163-177. [PMID: 38036777 DOI: 10.1007/s00424-023-02891-z] [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: 10/27/2023] [Revised: 11/21/2023] [Accepted: 11/23/2023] [Indexed: 12/02/2023]
Abstract
T-type calcium channels perform crucial physiological roles across a wide spectrum of tissues, spanning both neuronal and non-neuronal system. For instance, they serve as pivotal regulators of neuronal excitability, contribute to cardiac pacemaking, and mediate the secretion of hormones. These functions significantly hinge upon the intricate interplay of T-type channels with interacting proteins that modulate their expression and function at the plasma membrane. In this review, we offer a panoramic exploration of the current knowledge surrounding these T-type channel interactors, and spotlight certain aspects of their potential for drug-based therapeutic intervention.
Collapse
Affiliation(s)
- Norbert Weiss
- Department of Pathophysiology, Third Faculty of Medicine, Charles University, Prague, Czech Republic.
| | - Gerald W Zamponi
- Department of Clinical Neurosciences, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Canada
| |
Collapse
|
3
|
Maor G, Dubreuil RR, Feany MB. α-synuclein promotes neuronal dysfunction and death by disrupting the binding of ankyrin to ß-spectrin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.02.543481. [PMID: 37333277 PMCID: PMC10274672 DOI: 10.1101/2023.06.02.543481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
α-synuclein plays a key role in the pathogenesis of Parkinson's disease and related disorders, but critical interacting partners and molecular mechanisms mediating neurotoxicity are incompletely understood. We show that α-synuclein binds directly to ß-spectrin. Using males and females in a Drosophila model of α-synuclein-related disorders we demonstrate that ß-spectrin is critical for α-synuclein neurotoxicity. Further, the ankyrin binding domain of ß-spectrin is required for α-synuclein binding and neurotoxicity. A key plasma membrane target of ankyrin, Na+/K+ ATPase, is mislocalized when human α-synuclein is expressed in Drosophila. Accordingly, membrane potential is depolarized in α-synuclein transgenic fly brains. We examine the same pathway in human neurons and find that Parkinson's disease patient-derived neurons with a triplication of the α-synuclein locus show disruption of the spectrin cytoskeleton, mislocalization of ankyrin and Na+/K+ ATPase, and membrane potential depolarization. Our findings define a specific molecular mechanism by which elevated levels of α-synuclein in Parkinson's disease and related α-synucleinopathies leads to neuronal dysfunction and death.
Collapse
Affiliation(s)
- Gali Maor
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Ronald R. Dubreuil
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607
| | - Mel B. Feany
- Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, 20815
| |
Collapse
|
4
|
Lorenzo DN, Edwards RJ, Slavutsky AL. Spectrins: molecular organizers and targets of neurological disorders. Nat Rev Neurosci 2023; 24:195-212. [PMID: 36697767 PMCID: PMC10598481 DOI: 10.1038/s41583-022-00674-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/22/2022] [Indexed: 01/26/2023]
Abstract
Spectrins are cytoskeletal proteins that are expressed ubiquitously in the mammalian nervous system. Pathogenic variants in SPTAN1, SPTBN1, SPTBN2 and SPTBN4, four of the six genes encoding neuronal spectrins, cause neurological disorders. Despite their structural similarity and shared role as molecular organizers at the cell membrane, spectrins vary in expression, subcellular localization and specialization in neurons, and this variation partly underlies non-overlapping disease presentations across spectrinopathies. Here, we summarize recent progress in discerning the local and long-range organization and diverse functions of neuronal spectrins. We provide an overview of functional studies using mouse models, which, together with growing human genetic and clinical data, are helping to illuminate the aetiology of neurological spectrinopathies. These approaches are all critical on the path to plausible therapeutic solutions.
Collapse
Affiliation(s)
- Damaris N Lorenzo
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Reginald J Edwards
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Anastasia L Slavutsky
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
5
|
Maor G, Dubreuil RR, Feany MB. α-Synuclein Promotes Neuronal Dysfunction and Death by Disrupting the Binding of Ankyrin to β-Spectrin. J Neurosci 2023; 43:1614-1626. [PMID: 36653193 PMCID: PMC10008058 DOI: 10.1523/jneurosci.1922-22.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/30/2022] [Accepted: 12/08/2022] [Indexed: 01/20/2023] Open
Abstract
α-Synuclein plays a key role in the pathogenesis of Parkinson's disease and related disorders, but critical interacting partners and molecular mechanisms mediating neurotoxicity are incompletely understood. We show that α-synuclein binds directly to β-spectrin. Using males and females in a Drosophila model of α-synuclein-related disorders, we demonstrate that β-spectrin is critical for α-synuclein neurotoxicity. Further, the ankyrin binding domain of β-spectrin is required for α-synuclein binding and neurotoxicity. A key plasma membrane target of ankyrin, Na+/K+ ATPase, is mislocalized when human α-synuclein is expressed in Drosophila Accordingly, membrane potential is depolarized in α-synuclein transgenic fly brains. We examine the same pathway in human neurons and find that Parkinson's disease patient-derived neurons with a triplication of the α-synuclein locus show disruption of the spectrin cytoskeleton, mislocalization of ankyrin and Na+/K+ ATPase, and membrane potential depolarization. Our findings define a specific molecular mechanism by which elevated levels of α-synuclein in Parkinson's disease and related α-synucleinopathies lead to neuronal dysfunction and death.SIGNIFICANCE STATEMENT The small synaptic vesicle associate protein α-synuclein plays a critical role in the pathogenesis of Parkinson's disease and related disorders, but the disease-relevant binding partners of α-synuclein and proximate pathways critical for neurotoxicity require further definition. We show that α-synuclein binds directly to β-spectrin, a key cytoskeletal protein required for localization of plasma membrane proteins and maintenance of neuronal viability. Binding of α-synuclein to β-spectrin alters the organization of the spectrin-ankyrin complex, which is critical for localization and function of integral membrane proteins, including Na+/K+ ATPase. These finding outline a previously undescribed mechanism of α-synuclein neurotoxicity and thus suggest potential new therapeutic approaches in Parkinson's disease and related disorders.
Collapse
Affiliation(s)
- Gali Maor
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Ronald R Dubreuil
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois 60607
| | - Mel B Feany
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| |
Collapse
|
6
|
Zhou LX, Lin SW, Qiu RH, Lin L, Guo YF, Luo DS, Li YQ, Wang F. Blood-nerve barrier disruption and coagulation system activation induced by mechanical compression injury participate in the peripheral sensitization of trigeminal neuralgia. Front Mol Neurosci 2022; 15:1059980. [PMID: 36618827 PMCID: PMC9810503 DOI: 10.3389/fnmol.2022.1059980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Accepted: 11/28/2022] [Indexed: 12/24/2022] Open
Abstract
Introduction The aim of this study was to investigate the effect and possible mechanisms of the blood-nerve barrier (BNB) and the coagulation-anticoagulation system in modulating the mechanical allodynia in a trigeminal neuralgia (TN) rat model induced by chronic compression of the trigeminal root entry zone (TREZ). Methods Von Frey filaments were applied to determine the orofacial mechanical allodynia threshold. The BNB permeability was evaluated by Evans blue extravasation test. Immunohistochemical staining and laser confocal microscopy were used to measure the length of the depletion zones of the nodes of Ranvier in the TREZ, the diameter of nerve fibers and the length of the nodal gap. The transcriptional levels of prothrombin and endogenous thrombin inhibitor protease nexin-1 (PN-1) in the TREZ of TN rats were assessed by RT-qPCR. A Western blotting assay was performed to detect the expression of paranodal proteins neurofascin-155 (NF155) and neurofascin-125 (NF125) in the TREZ. The spatiotemporal expression pattern of thrombin activated receptor (i.e. protease activated receptor 1, PAR1) in TREZ were defined by immunostaining and immunoblotting assays. PAR1 receptor inhibitors SCH79797 were administrated to TN rats to analyze the effect of thrombin-PAR1 on orofacial hyperalgesia. Results A compression injury of a rat's TREZ successfully induced TN-like behavior and was accompanied by the destruction of the permeability of the BNB and the promotion of prothrombin and thrombin inhibitor protease nexin-1 (PN-1) expression. The expression of the paranodal proteins neurofascin-155 (NF155) and neurofascin-125 (NF125) was increased, while the nodal gap length of the nodes of Ranvier was widened and the length of node-depleted zones was shortened. Moreover, the expression of PAR1 within the TREZ was upregulated at an early stage of TN, and administration of the PAR1 antagonist SCH79797 effectively ameliorated orofacial mechanical allodynia. Conclusion A compression injury of the TREZ increased the permeability of the BNB and induced disturbances in the local coagulation-anticoagulation system, concomitant with the structural changes in the nodes of Ranvier, thrombin-PAR1 may play a critical role in modulating orofacial mechanical hyperalgesia in a TN rat model.
Collapse
Affiliation(s)
- Lu-Xi Zhou
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Shao-Wei Lin
- Department of Epidemiology and Health Statistics, Fujian Provincial Key Laboratory of Environment Factors and Cancer, School of Public Health, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Rong-Hui Qiu
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Ling Lin
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China,Public Technology Service Center, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Yue-Feng Guo
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Dao-Shu Luo
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China,Dao-Shu Luo,
| | - Yun-Qing Li
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China,Public Technology Service Center, Fujian Medical University, Fuzhou, Fujian Province, China,Yun-Qing Li,
| | - Feng Wang
- Laboratory of Clinical Applied Anatomy, Key Laboratory of Brain Aging and Neurodegenerative Diseases, School of Basic Medical Sciences, Fujian Medical University, Fuzhou, Fujian Province, China,*Correspondence: Feng Wang,
| |
Collapse
|
7
|
Bartley CM, Ngo TT, Alvarenga BD, Kung AF, Teliska LH, Sy M, DeRisi JL, Rasband MN, Pittock SJ, Dubey D, Wilson MR, Pleasure SJ. βIV-Spectrin Autoantibodies in 2 Individuals With Neuropathy of Possible Paraneoplastic Origin: A Case Series. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2022; 9:e1188. [PMID: 35581007 PMCID: PMC9128026 DOI: 10.1212/nxi.0000000000001188] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 04/18/2022] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To identify the autoantigen in 2 individuals with possible seronegative paraneoplastic neuropathy. METHODS Serum and CSF were screened by tissue-based assay and panned for candidate autoantibodies by phage display immunoprecipitation sequencing (PhIP-Seq). The candidate antigen was validated by immunostaining knockout tissue and HEK 293T cell-based assay. RESULTS Case 1 presented with gait instability, distal lower extremity numbness, and paresthesias after a recent diagnosis of serous uterine and fallopian carcinoma. Case 2 had a remote history of breast adenocarcinoma and presented with gait instability, distal lower extremity numbness, and paresthesias that progressed to generalized weakness. CSF and serum from both patients immunostained the axon initial segment (AIS) and node of Ranvier (NoR) of mice and enriched βIV-spectrin by PhIP-Seq. Patient CSF and serum failed to immunostain NoRs in dorsal root sensory neurons from βI/βIV-deficient mice. βIV-spectrin autoantibodies were confirmed by overexpression of AIS and nodal βIV-spectrin isoforms Σ1 and Σ6 by a cell-based assay. βIV-spectrin was not enriched in a combined 4,815 PhIP-Seq screens of healthy and other neurologic disease patients. DISCUSSION Therefore, βIV-spectrin autoantibodies may be a marker of paraneoplastic neuropathy. CLASSIFICATION OF EVIDENCE This study provides Class IV evidence that βIV-spectrin antibodies are specific autoantibody biomarkers for paraneoplastic neuropathy.
Collapse
Affiliation(s)
| | | | - Bonny D. Alvarenga
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Andrew F. Kung
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Lindsay H. Teliska
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Michael Sy
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Joseph L. DeRisi
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Matthew N. Rasband
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Sean J. Pittock
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Divyanshu Dubey
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Michael R. Wilson
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| | - Samuel J. Pleasure
- From the Weill Institute for Neurosciences (C.M.B., T.T.N., B.D.A., M.R.W., S.J. Pleasure), Department of Psychiatry and Behavioral Sciences (C.M.B., T.T.N.), Department of Neurology (B.D.A., M.R.W., S.J. Pleasure), UCSF School of Medicine (A.F.K.), University of California, San Francisco; Department of Neuroscience (L.H.T., M.N.R.), Baylor College of Medicine, Houston, TX; Department of Neurology (M.S.), University of California, Irvine; Chan Zuckerberg Biohub (J.L.D.), San Francisco, CA; Department of Biochemistry and Biophysics (J.L.D.), University of California, San Francisco; Department of Laboratory Medicine and Pathology (S.J. Pittock, D.D.), Department of Neurology (S.J. Pittock, D.D.), andCenter MS and Autoimmune Neurology (S.J. Pittock, D.D.), Mayo Clinic, Rochester, MN
| |
Collapse
|
8
|
Loss of β4-spectrin impairs Na v channel clustering at the heminode and temporal fidelity of presynaptic spikes in developing auditory brain. Sci Rep 2022; 12:5854. [PMID: 35393465 PMCID: PMC8991253 DOI: 10.1038/s41598-022-09856-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 03/15/2022] [Indexed: 01/21/2023] Open
Abstract
Beta-4 (β4)-spectrin, encoded by the gene Sptbn4, is a cytoskeleton protein found at nodes and the axon initial segments (AIS). Sptbn4 mutations are associated with myopathy, neuropathy, and auditory deficits in humans. Related to auditory dysfunction, however, the expression and roles of β4-spectrin at axon segments along the myelinated axon in the developing auditory brain are not well explored. We found during postnatal development, β4-spectrin is critical for voltage-gated sodium channel (Nav) clustering at the heminode along the nerve terminal, but not for the formation of nodal and AIS structures in the auditory brainstem. Presynaptic terminal recordings in Sptbn4geo mice, β4-spectrin null mice, showed an elevated threshold of action potential and increased failures during action potential train at high-frequency. Sptbn4geo mice exhibited a slower central conduction and showed no startle responses, but had normal cochlear function. Taken together, the lack of β4-spectrin impairs Nav clustering at the heminode along the nerve terminal and the temporal fidelity and reliability of presynaptic spikes, leading to central auditory processing deficits during postnatal development.
Collapse
|
9
|
de Clauser L, Kappert C, Sondermann JR, Gomez-Varela D, Flatters SJL, Schmidt M. Proteome and Network Analysis Provides Novel Insights Into Developing and Established Chemotherapy-Induced Peripheral Neuropathy. Front Pharmacol 2022; 13:818690. [PMID: 35250568 PMCID: PMC8895144 DOI: 10.3389/fphar.2022.818690] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/12/2022] [Indexed: 01/09/2023] Open
Abstract
Chemotherapy-induced peripheral neuropathy (CIPN) is a debilitating side-effect of cancer therapies. So far, the development of CIPN cannot be prevented, neither can established CIPN be reverted, often leading to the cessation of necessary chemotherapy. Thus, there is an urgent need to explore the mechanistic basis of CIPN to facilitate its treatment. Here we used an integrated approach of quantitative proteome profiling and network analysis in a clinically relevant rat model of paclitaxel-induced peripheral neuropathy. We analysed lumbar rat DRG at two critical time points: (1) day 7, right after cessation of paclitaxel treatment, but prior to neuropathy development (pre-CIPN); (2) 4 weeks after paclitaxel initiation, when neuropathy has developed (peak-CIPN). In this way we identified a differential protein signature, which shows how changes in the proteome correlate with the development and maintenance of CIPN, respectively. Extensive biological pathway and network analysis reveals that, at pre-CIPN, regulated proteins are prominently implicated in mitochondrial (dys)function, immune signalling, neuronal damage/regeneration, and neuronal transcription. Orthogonal validation in an independent rat cohort confirmed the increase of β-catenin (CTNNB1) at pre-CIPN. More importantly, detailed analysis of protein networks associated with β-catenin highlights translationally relevant and potentially druggable targets. Overall, this study demonstrates the enormous value of combining animal behaviour with proteome and network analysis to provide unprecedented insights into the molecular basis of CIPN. In line with emerging approaches of network medicine our results highlight new avenues for developing improved therapeutic options aimed at preventing and treating CIPN.
Collapse
Affiliation(s)
- Larissa de Clauser
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
- Institute for Biomedicine, Eurac Research, Affiliated Institute of the University of Lübeck, Bolzano, Italy
- *Correspondence: Larissa de Clauser, ; Manuela Schmidt,
| | - Christin Kappert
- Max Planck Institute of Experimental Medicine, Goettingen, Germany
| | - Julia R. Sondermann
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
| | - David Gomez-Varela
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
| | - Sarah J. L. Flatters
- Wolfson Centre for Age-Related Diseases, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Manuela Schmidt
- Division of Pharmacology and Toxicology, Department of Pharmaceutical Sciences, University of Vienna, Vienna, Austria
- *Correspondence: Larissa de Clauser, ; Manuela Schmidt,
| |
Collapse
|
10
|
Zhang C, Joshi A, Liu Y, Sert O, Haddix SG, Teliska LH, Rasband A, Rodney GG, Rasband MN. Ankyrin-dependent Na + channel clustering prevents neuromuscular synapse fatigue. Curr Biol 2021; 31:3810-3819.e4. [PMID: 34289389 DOI: 10.1016/j.cub.2021.06.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/09/2021] [Accepted: 06/17/2021] [Indexed: 01/18/2023]
Abstract
Skeletal muscle contraction depends on activation of clustered acetylcholine receptors (AchRs) and muscle-specific Na+ channels (Nav1.4). Some Nav1.4 channels are highly enriched at the neuromuscular junction (NMJ), and their clustering is thought to be essential for effective muscle excitation. However, this has not been experimentally tested, and how NMJ Na+ channels are clustered is unknown. Here, using muscle-specific ankyrinR, ankyrinB, and ankyrinG single, double, and triple-conditional knockout mice, we show that Nav1.4 channels fail to cluster only after deletion of all three ankyrins. Remarkably, ankyrin-deficient muscles have normal NMJ morphology, AchR clustering, sarcolemmal levels of Nav1.4, and muscle force, and they show no indication of degeneration. However, mice lacking clustered NMJ Na+ channels have significantly reduced levels of motor activity and their NMJs rapidly fatigue after repeated nerve-dependent stimulation. Thus, the triple redundancy of ankyrins facilitates NMJ Na+ channel clustering to prevent neuromuscular synapse fatigue.
Collapse
Affiliation(s)
- Chuansheng Zhang
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Abhijeet Joshi
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yanhong Liu
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ozlem Sert
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Seth G Haddix
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lindsay H Teliska
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Anne Rasband
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - George G Rodney
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Matthew N Rasband
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.
| |
Collapse
|
11
|
|
12
|
Regulation of Cardiac Conduction and Arrhythmias by Ankyrin/Spectrin-Based Macromolecular Complexes. J Cardiovasc Dev Dis 2021; 8:jcdd8050048. [PMID: 33946725 PMCID: PMC8146975 DOI: 10.3390/jcdd8050048] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/15/2021] [Accepted: 04/19/2021] [Indexed: 12/19/2022] Open
Abstract
The cardiac conduction system is an extended network of excitable tissue tasked with generation and propagation of electrical impulses to signal coordinated contraction of the heart. The fidelity of this system depends on the proper spatio-temporal regulation of ion channels in myocytes throughout the conduction system. Importantly, inherited or acquired defects in a wide class of ion channels has been linked to dysfunction at various stages of the conduction system resulting in life-threatening cardiac arrhythmia. There is growing appreciation of the role that adapter and cytoskeletal proteins play in organizing ion channel macromolecular complexes critical for proper function of the cardiac conduction system. In particular, members of the ankyrin and spectrin families have emerged as important nodes for normal expression and regulation of ion channels in myocytes throughout the conduction system. Human variants impacting ankyrin/spectrin function give rise to a broad constellation of cardiac arrhythmias. Furthermore, chronic neurohumoral and biomechanical stress promotes ankyrin/spectrin loss of function that likely contributes to conduction disturbances in the setting of acquired cardiac disease. Collectively, this review seeks to bring attention to the significance of these cytoskeletal players and emphasize the potential therapeutic role they represent in a myriad of cardiac disease states.
Collapse
|
13
|
Prokop A. Cytoskeletal organization of axons in vertebrates and invertebrates. J Cell Biol 2021; 219:151734. [PMID: 32369543 PMCID: PMC7337489 DOI: 10.1083/jcb.201912081] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 12/11/2022] Open
Abstract
The maintenance of axons for the lifetime of an organism requires an axonal cytoskeleton that is robust but also flexible to adapt to mechanical challenges and to support plastic changes of axon morphology. Furthermore, cytoskeletal organization has to adapt to axons of dramatically different dimensions, and to their compartment-specific requirements in the axon initial segment, in the axon shaft, at synapses or in growth cones. To understand how the cytoskeleton caters to these different demands, this review summarizes five decades of electron microscopic studies. It focuses on the organization of microtubules and neurofilaments in axon shafts in both vertebrate and invertebrate neurons, as well as the axon initial segments of vertebrate motor- and interneurons. Findings from these ultrastructural studies are being interpreted here on the basis of our contemporary molecular understanding. They strongly suggest that axon architecture in animals as diverse as arthropods and vertebrates is dependent on loosely cross-linked bundles of microtubules running all along axons, with only minor roles played by neurofilaments.
Collapse
Affiliation(s)
- Andreas Prokop
- School of Biology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| |
Collapse
|
14
|
Stevens SR, Rasband MN. Ankyrins and neurological disease. Curr Opin Neurobiol 2021; 69:51-57. [PMID: 33485190 DOI: 10.1016/j.conb.2021.01.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/06/2021] [Accepted: 01/08/2021] [Indexed: 12/11/2022]
Abstract
Ankyrins are scaffolding proteins widely expressed throughout the nervous system. Ankyrins recruit diverse membrane proteins, including ion channels and cell adhesion molecules, into specialized subcellular membrane domains. These domains are stabilized by ankyrins interacting with the spectrin cytoskeleton. Ankyrin genes are highly associated with a number of neurological disorders, including Alzheimer's disease, schizophrenia, autism spectrum disorders, and bipolar disorder. Here, we discuss ankyrin function and their role in neurological disease. We propose mutations in ankyrins contribute to disease through two primary mechanisms: 1) altered neuronal excitability by disrupting ion channel clustering at key excitable domains, and 2) altered neuronal connectivity via impaired stabilization of membrane proteins.
Collapse
Affiliation(s)
- Sharon R Stevens
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Matthew N Rasband
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA.
| |
Collapse
|
15
|
Abstract
The nodes of Ranvier have clustered Na+ and K+ channels necessary for rapid and efficient axonal action potential conduction. However, detailed mechanisms of channel clustering have only recently been identified: they include two independent axon-glia interactions that converge on distinct axonal cytoskeletons. Here, we discuss how glial cell adhesion molecules and the extracellular matrix molecules that bind them assemble combinations of ankyrins, spectrins and other cytoskeletal scaffolding proteins, which cluster ion channels. We present a detailed molecular model, incorporating these overlapping mechanisms, to explain how the nodes of Ranvier are assembled in both the peripheral and central nervous systems.
Collapse
|
16
|
Accumulation of Neurofascin at Nodes of Ranvier Is Regulated by a Paranodal Switch. J Neurosci 2020; 40:5709-5723. [PMID: 32554548 DOI: 10.1523/jneurosci.0830-19.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 04/29/2020] [Accepted: 06/02/2020] [Indexed: 12/18/2022] Open
Abstract
The paranodal junctions flank mature nodes of Ranvier and provide a barrier between ion channels at the nodes and juxtaparanodes. These junctions also promote node assembly and maintenance by mechanisms that are poorly understood. Here, we examine their role in the accumulation of NF186, a key adhesion molecule of PNS and CNS nodes. We previously showed that NF186 is initially targeted/accumulates via its ectodomain to forming PNS (hemi)nodes by diffusion trapping, whereas it is later targeted to mature nodes by a transport-dependent mechanism mediated by its cytoplasmic segment. To address the role of the paranodes in this switch, we compared accumulation of NF186 ectodomain and cytoplasmic domain constructs in WT versus paranode defective (i.e., Caspr-null) mice. Both pathways are affected in the paranodal mutants. In the PNS of Caspr-null mice, diffusion trapping mediated by the NF186 ectodomain aberrantly persists into adulthood, whereas the cytoplasmic domain/transport-dependent targeting is impaired. In contrast, accumulation of NF186 at CNS nodes does not undergo a switch; it is predominantly targeted to both forming and mature CNS nodes via its cytoplasmic domain and requires intact paranodes. Fluorescence recovery after photobleaching analysis indicates that the paranodes provide a membrane diffusion barrier that normally precludes diffusion of NF186 to nodes. Linkage of paranodal proteins to the underlying cytoskeleton likely contributes to this diffusion barrier based on 4.1B and βII spectrin expression in Caspr-null mice. Together, these results implicate the paranodes as membrane diffusion barriers that regulate targeting to nodes and highlight differences in the assembly of PNS and CNS nodes.SIGNIFICANCE STATEMENT Nodes of Ranvier are essential for effective saltatory conduction along myelinated axons. A major question is how the various axonal proteins that comprise the multimeric nodal complex accumulate at this site. Here we examine how targeting of NF186, a key nodal adhesion molecule, is regulated by the flanking paranodal junctions. We show that the transition from diffusion-trapping to transport-dependent accumulation of NF186 requires the paranodal junctions. We also demonstrate that these junctions are a barrier to diffusion of axonal proteins into the node and highlight differences in PNS and CNS node assembly. These results provide new insights into the mechanism of node assembly and the pathophysiology of neurologic disorders in which impaired paranodal function contributes to clinical disability.
Collapse
|
17
|
Li J, Chen K, Zhu R, Zhang M. Structural Basis Underlying Strong Interactions between Ankyrins and Spectrins. J Mol Biol 2020; 432:3838-3850. [DOI: 10.1016/j.jmb.2020.04.023] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Revised: 04/18/2020] [Accepted: 04/23/2020] [Indexed: 01/06/2023]
|
18
|
Liu CH, Seo R, Ho TSY, Stankewich M, Mohler PJ, Hund TJ, Noebels JL, Rasband MN. β spectrin-dependent and domain specific mechanisms for Na + channel clustering. eLife 2020; 9:e56629. [PMID: 32425157 PMCID: PMC7237202 DOI: 10.7554/elife.56629] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/07/2020] [Indexed: 12/23/2022] Open
Abstract
Previously, we showed that a hierarchy of spectrin cytoskeletal proteins maintains nodal Na+ channels (Liu et al., 2020). Here, using mice lacking β1, β4, or β1/β4 spectrins, we show this hierarchy does not function at axon initial segments (AIS). Although β1 spectrin, together with AnkyrinR (AnkR), compensates for loss of nodal β4 spectrin, it cannot compensate at AIS. We show AnkR lacks the domain necessary for AIS localization. Whereas loss of β4 spectrin causes motor impairment and disrupts AIS, loss of β1 spectrin has no discernable effect on central nervous system structure or function. However, mice lacking both neuronal β1 and β4 spectrin show exacerbated nervous system dysfunction compared to mice lacking β1 or β4 spectrin alone, including profound disruption of AIS Na+ channel clustering, progressive loss of nodal Na+ channels, and seizures. These results further define the important role of AIS and nodal spectrins for nervous system function.
Collapse
Affiliation(s)
- Cheng-Hsin Liu
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Program in Developmental Biology, Baylor College of MedicineHoustonUnited States
| | - Ryan Seo
- Department of Neurology, Baylor College of MedicineHoustonUnited States
| | - Tammy Szu-Yu Ho
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
| | | | - Peter J Mohler
- Department of Physiology and Cell Biology, The Ohio State UniversityColumbusUnited States
| | - Thomas J Hund
- Department of Biomedical Engineering, The Ohio State UniversityColumbusUnited States
| | - Jeffrey L Noebels
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Department of Neurology, Baylor College of MedicineHoustonUnited States
| | - Matthew N Rasband
- Department of Neuroscience, Baylor College of MedicineHoustonUnited States
- Program in Developmental Biology, Baylor College of MedicineHoustonUnited States
| |
Collapse
|