1
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Gallo PN, Mihelc E, Eisert R, Bradshaw GA, Dimek F, Leffler A, Kalocsay M, Moiseenkova-Bell V. The dynamic TRPV2 ion channel proximity proteome reveals functional links of calcium flux with cellular adhesion factors NCAM and L1CAM in neurite outgrowth. Cell Calcium 2024; 121:102894. [PMID: 38728789 DOI: 10.1016/j.ceca.2024.102894] [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: 01/06/2024] [Revised: 04/24/2024] [Accepted: 04/25/2024] [Indexed: 05/12/2024]
Abstract
TRPV2 voltage-insensitive, calcium-permeable ion channels play important roles in cancer progression, immune response, and neuronal development. Despite TRPV2's physiological impact, underlying endogenous proteins mediating TRPV2 responses and affected signaling pathways remain elusive. Using quantitative peroxidase-catalyzed (APEX2) proximity proteomics we uncover dynamic changes in the TRPV2-proximal proteome and identify calcium signaling and cell adhesion factors recruited to the molecular channel neighborhood in response to activation. Quantitative TRPV2 proximity proteomics further revealed activation-induced enrichment of protein clusters with biological functions in neural and cellular projection. We demonstrate a functional connection between TRPV2 and the neural immunoglobulin cell adhesion molecules NCAM and L1CAM. NCAM and L1CAM stimulation robustly induces TRPV2 [Ca2+]I flux in neuronal PC12 cells and this TRPV2-specific [Ca2+]I flux requires activation of the protein kinase PKCα. TRPV2 expression directly impacts neurite lengths that are modulated by NCAM or L1CAM stimulation. Hence, TRPV2's calcium signaling plays a previously undescribed, yet vital role in cell adhesion, and TRPV2 calcium flux and neurite development are intricately linked via NCAM and L1CAM cell adhesion proteins.
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Affiliation(s)
- Pamela N Gallo
- University of Pennsylvania, Systems Pharmacology and Translational Therapeutics, Philadelphia, PA, USA
| | - Elaine Mihelc
- University of Pennsylvania, Systems Pharmacology and Translational Therapeutics, Philadelphia, PA, USA
| | - Robyn Eisert
- Harvard Medical School, Department of Biological Chemistry and Molecular Pharmacology, Boston, MA, USA
| | - Gary A Bradshaw
- Harvard Medical School, Laboratory of Systems Pharmacology, Boston, MA, USA
| | - Florian Dimek
- Hannover Medical School, Department of Anesthesiology and Intensive Care Medicine, Hannover, Germany
| | - Andreas Leffler
- Hannover Medical School, Department of Anesthesiology and Intensive Care Medicine, Hannover, Germany
| | - Marian Kalocsay
- The University of Texas MD Anderson Cancer Center, Department of Experimental Radiation Oncology, Houston, TX, USA.
| | - Vera Moiseenkova-Bell
- University of Pennsylvania, Systems Pharmacology and Translational Therapeutics, Philadelphia, PA, USA.
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2
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Liu H, Welburn JPI. A circle of life: platelet and megakaryocyte cytoskeleton dynamics in health and disease. Open Biol 2024; 14:240041. [PMID: 38835242 DOI: 10.1098/rsob.240041] [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: 02/19/2024] [Accepted: 04/24/2024] [Indexed: 06/06/2024] Open
Abstract
Platelets are blood cells derived from megakaryocytes that play a central role in regulating haemostasis and vascular integrity. The microtubule cytoskeleton of megakaryocytes undergoes a critical dynamic reorganization during cycles of endomitosis and platelet biogenesis. Quiescent platelets have a discoid shape maintained by a marginal band composed of microtubule bundles, which undergoes remarkable remodelling during platelet activation, driving shape change and platelet function. Disrupting or enhancing this process can cause platelet dysfunction such as bleeding disorders or thrombosis. However, little is known about the molecular mechanisms underlying the reorganization of the cytoskeleton in the platelet lineage. Recent studies indicate that the emergence of a unique platelet tubulin code and specific pathogenic tubulin mutations cause platelet defects and bleeding disorders. Frequently, these mutations exhibit dominant negative effects, offering valuable insights into both platelet disease mechanisms and the functioning of tubulins. This review will highlight our current understanding of the role of the microtubule cytoskeleton in the life and death of platelets, along with its relevance to platelet disorders.
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Affiliation(s)
- Haonan Liu
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Julie P I Welburn
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
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3
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Coker ZN, Troyanova-Wood M, Steelman ZA, Ibey BL, Bixler JN, Scully MO, Yakovlev VV. Brillouin microscopy monitors rapid responses in subcellular compartments. PHOTONIX 2024; 5:9. [PMID: 38618142 PMCID: PMC11006764 DOI: 10.1186/s43074-024-00123-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 02/12/2024] [Accepted: 03/11/2024] [Indexed: 04/16/2024]
Abstract
Measurements and imaging of the mechanical response of biological cells are critical for understanding the mechanisms of many diseases, and for fundamental studies of energy, signal and force transduction. The recent emergence of Brillouin microscopy as a powerful non-contact, label-free way to non-invasively and non-destructively assess local viscoelastic properties provides an opportunity to expand the scope of biomechanical research to the sub-cellular level. Brillouin spectroscopy has recently been validated through static measurements of cell viscoelastic properties, however, fast (sub-second) measurements of sub-cellular cytomechanical changes have yet to be reported. In this report, we utilize a custom multimodal spectroscopy system to monitor for the very first time the rapid viscoelastic response of cells and subcellular structures to a short-duration electrical impulse. The cytomechanical response of three subcellular structures - cytoplasm, nucleoplasm, and nucleoli - were monitored, showing distinct mechanical changes despite an identical stimulus. Through this pioneering transformative study, we demonstrate the capability of Brillouin spectroscopy to measure rapid, real-time biomechanical changes within distinct subcellular compartments. Our results support the promising future of Brillouin spectroscopy within the broad scope of cellular biomechanics.
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Affiliation(s)
- Zachary N. Coker
- Department of Physics & Astronomy, Texas A&M University, 4242 TAMU, College Station, TX 77843 USA
- SAIC, Fort Sam Houston, TX 78234 USA
| | | | - Zachary A. Steelman
- Air Force Research Laboratory, JBSA Fort Sam Houston, Fort Sam Houston, TX 78234 USA
| | - Bennett L. Ibey
- Air Force Research Laboratory, JBSA Fort Sam Houston, Fort Sam Houston, TX 78234 USA
| | - Joel N. Bixler
- Air Force Research Laboratory, JBSA Fort Sam Houston, Fort Sam Houston, TX 78234 USA
| | - Marlan O. Scully
- Department of Physics & Astronomy, Texas A&M University, 4242 TAMU, College Station, TX 77843 USA
- Institute for Quantum Science and Engineering, Texas A&M University, College Station, TX 77843 USA
| | - Vladislav V. Yakovlev
- Department of Physics & Astronomy, Texas A&M University, 4242 TAMU, College Station, TX 77843 USA
- Institute for Quantum Science and Engineering, Texas A&M University, College Station, TX 77843 USA
- Department of Biomedical Engineering, Texas A&M University, 3120 TAMU, 101 Bizzell Street, College Station, TX 77843 USA
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4
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Krieg JL, Leonard AV, Turner RJ, Corrigan F. Identifying the Phenotypes of Diffuse Axonal Injury Following Traumatic Brain Injury. Brain Sci 2023; 13:1607. [PMID: 38002566 PMCID: PMC10670443 DOI: 10.3390/brainsci13111607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 11/15/2023] [Accepted: 11/17/2023] [Indexed: 11/26/2023] Open
Abstract
Diffuse axonal injury (DAI) is a significant feature of traumatic brain injury (TBI) across all injury severities and is driven by the primary mechanical insult and secondary biochemical injury phases. Axons comprise an outer cell membrane, the axolemma which is anchored to the cytoskeletal network with spectrin tetramers and actin rings. Neurofilaments act as space-filling structural polymers that surround the central core of microtubules, which facilitate axonal transport. TBI has differential effects on these cytoskeletal components, with axons in the same white matter tract showing a range of different cytoskeletal and axolemma alterations with different patterns of temporal evolution. These require different antibodies for detection in post-mortem tissue. Here, a comprehensive discussion of the evolution of axonal injury within different cytoskeletal elements is provided, alongside the most appropriate methods of detection and their temporal profiles. Accumulation of amyloid precursor protein (APP) as a result of disruption of axonal transport due to microtubule failure remains the most sensitive marker of axonal injury, both acutely and chronically. However, a subset of injured axons demonstrate different pathology, which cannot be detected via APP immunoreactivity, including degradation of spectrin and alterations in neurofilaments. Furthermore, recent work has highlighted the node of Ranvier and the axon initial segment as particularly vulnerable sites to axonal injury, with loss of sodium channels persisting beyond the acute phase post-injury in axons without APP pathology. Given the heterogenous response of axons to TBI, further characterization is required in the chronic phase to understand how axonal injury evolves temporally, which may help inform pharmacological interventions.
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Affiliation(s)
- Justin L Krieg
- Translational Neuropathology Laboratory, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5000, Australia
| | - Anna V Leonard
- Translational Neuropathology Laboratory, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5000, Australia
| | - Renée J Turner
- Translational Neuropathology Laboratory, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5000, Australia
| | - Frances Corrigan
- Translational Neuropathology Laboratory, School of Biomedicine, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide 5000, Australia
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5
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Kouba S, Buscaglia P, Guéguinou M, Ibrahim S, Félix R, Guibon R, Fromont G, Pigat N, Capiod T, Vandier C, Mignen O, Potier-Cartereau M. Pivotal role of the ORAI3-STIM2 complex in the control of mitotic death and prostate cancer cell cycle progression. Cell Calcium 2023; 115:102794. [PMID: 37597301 DOI: 10.1016/j.ceca.2023.102794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/27/2023] [Accepted: 08/12/2023] [Indexed: 08/21/2023]
Abstract
Prostate cancer (PCa) represents one of the most frequent diagnosed cancer in males worldwide. Due to routine screening tests and the efficiency of available treatments, PCa-related deaths have significantly decreased over the past decades. However, PCa remains a critical threat if detected at a late stage in which, cancer cells would have already detached from the primary tumor to spread and invade other parts of the body. Calcium (Ca2+) channels and their protein regulators are now considered as hallmarks of cancer and some of them have been well examined in PCa. Among these Ca2+ channels, isoform 3 of the ORAI channel family has been shown to regulate the proliferation of PCa cells via the Arachidonic Acid-mediated Ca2+ entry, requiring the involvement of STIM1 (Stromal Interaction Molecule 1). Still, no study has yet demonstrated a role of the "neglected" STIM2 isoform in PCa or if it may interact with ORAI3 to promote an oncogenic behavior. In this study, we demonstrate that ORAI3 and STIM2 are upregulated in human PCa tissues. In old KIMAP (Knock-In Mouse Prostate Adenocarcinoma) mice, ORAI3 and STIM2 mRNA levels were significantly higher than ORAI1 and STIM1. In vitro, we show that ORAI3-STIM2 interact under basal conditions in PC-3 cells. ORAI3 silencing increased Store Operated Ca2+ Entry (SOCE) and induced a significant increase of the cell population in G2/M phase of the cell cycle, consistent with the role of ORAI3 as a negative regulator of SOCE. Higher expression levels of CDK1-Y15/Cyclin B1 were detected and mitotic arrest-related death occurred after ORAI3 silencing, which resulted in activating Bax/Bcl-2-mediated apoptotic pathway and caspase-8 activation and cleavage. STIM2 and ORAI3 expression increased in M phase while STIM1 expression and SOCE amplitude significantly decreased. Taken together, ORAI3 -STIM2 complex allows a successful progression through mitosis of PCa cells by evading mitotic catastrophe.
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Affiliation(s)
- Sana Kouba
- INSERM U1069, N2C: Nutrition, Croissance et Cancer, University of Tours, Tours, France
| | - Paul Buscaglia
- INSERM U1227, LBAI: Lymphocytes B, Autoimmunité et Immunotherapies, University of Bretagne Occidentale, Brest, France
| | - Maxime Guéguinou
- INSERM U1069, N2C: Nutrition, Croissance et Cancer, University of Tours, Tours, France
| | - Sajida Ibrahim
- EA 7501, University of Tours - ERL 7001 LNOx - CNRS, GICC: Groupe Innovation et Ciblage Cellulaire, Tours, France
| | - Romain Félix
- INSERM U1227, LBAI: Lymphocytes B, Autoimmunité et Immunotherapies, University of Bretagne Occidentale, Brest, France
| | - Roseline Guibon
- INSERM U1069, N2C: Nutrition, Croissance et Cancer, University of Tours, Tours, France; Service d'Anatomie et cytologie pathologiques, Bretonneau, Centre Hospitalier Régional et Universitaire, Tours, France
| | - Gaëlle Fromont
- INSERM U1069, N2C: Nutrition, Croissance et Cancer, University of Tours, Tours, France; Service d'Anatomie et cytologie pathologiques, Bretonneau, Centre Hospitalier Régional et Universitaire, Tours, France
| | - Natascha Pigat
- INSERM U1151, Institut Necker Enfants Malades, Universiy of Paris, 160 rue de Vaugirard, Paris 75015 France
| | - Thierry Capiod
- INSERM U1151, Institut Necker Enfants Malades, Universiy of Paris, 160 rue de Vaugirard, Paris 75015 France
| | - Christophe Vandier
- INSERM U1069, N2C: Nutrition, Croissance et Cancer, University of Tours, Tours, France
| | - Olivier Mignen
- INSERM U1227, LBAI: Lymphocytes B, Autoimmunité et Immunotherapies, University of Bretagne Occidentale, Brest, France.
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6
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Dougherty LL, Avasthi P. Determinants of cytoplasmic microtubule depolymerization during ciliogenesis in Chlamydomonas reinhardtii. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.07.536038. [PMID: 37066348 PMCID: PMC10104144 DOI: 10.1101/2023.04.07.536038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/18/2023]
Abstract
At the core of cilia are microtubules which are important for establishing length and assisting ciliary assembly and disassembly; however, another role for microtubule regulation on ciliogenesis lies outside of the cilium. The microtubule cytoskeleton is a highly dynamic structure which polymerizes and depolymerizes rapidly to assist in cellular processes. These processes have been studied across various organisms with chemical as well as genetic perturbations. However, these have generated conflicting data in terms of the role of cytoplasmic microtubules (CytoMTs) and free tubulin dynamics during ciliogenesis. Here we look at the relationship between ciliogenesis and cytoplasmic microtubule dynamics in Chlamydomonas reinhardtii using chemical and mechanical perturbations. We find that not only can stabilized CytoMTs allow for normal ciliary assembly, but high calcium concentrations and low pH-induced deciliation cause CytoMTs to depolymerize separately from ciliary shedding. In addition, we find that ciliary shedding through mechanical shearing, cilia regenerate earlier despite intact CytoMTs. Our data suggests that cytoplasmic microtubules are not a sink for a limiting pool of cytoplasmic tubulin in Chlamydomonas, depolymerization that occurs following deciliation is a consequence rather than a requirement for ciliogenesis, and intact CytoMTs in the cytoplasm and the proximal cilium support more efficient ciliary assembly.
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Affiliation(s)
- Larissa L Dougherty
- Biochemistry and Cell Biology Department, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire
| | - Prachee Avasthi
- Biochemistry and Cell Biology Department, Geisel School of Medicine at Dartmouth College, Hanover, New Hampshire
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7
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Arora V, Li T, Kumari S, Wang S, Asgar J, Chung MK. Capsaicin-induced depolymerization of axonal microtubules mediates analgesia for trigeminal neuropathic pain. Pain 2022; 163:1479-1488. [PMID: 34724681 PMCID: PMC9046530 DOI: 10.1097/j.pain.0000000000002529] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 10/05/2021] [Accepted: 10/25/2021] [Indexed: 11/26/2022]
Abstract
ABSTRACT Capsaicin is a specific agonist of transient receptor potential vanilloid 1 (TRPV1), which is enriched in nociceptors. Capsaicin not only produces acute pain but also leads to long-lasting analgesia in patients with chronic pain. Although capsaicin-induced TRPV1 and Ca 2+ /calpain-dependent ablation of axonal terminals is necessary for long-lasting analgesia, the mechanisms underlying capsaicin-induced ablation of axonal terminals and its association with analgesia are not fully understood. Microtubules are composed of tubulin polymers and serve as a main axonal cytoskeleton maintaining axonal integrity. In this study, we hypothesized that capsaicin would increase the depolymerization of microtubules and lead to axonal ablation and analgesia for trigeminal neuropathic pain. Paclitaxel, a microtubule stabilizer, decreased capsaicin-induced ablation of axonal terminals in time-lapsed imaging in vitro. Capsaicin increases free tubulin in dissociated sensory neurons, which was inhibited by paclitaxel. Consistently, subcutaneous injection of paclitaxel prevented capsaicin-induced axonal ablation in the hind paw skin. Capsaicin administration to the facial skin produced analgesia for mechanical hyperalgesia in mice with chronic constriction injury of the infraorbital nerve, which was prevented by the coadministration of paclitaxel and capsaicin. Whole-mount staining of facial skin showed that paclitaxel reduced capsaicin-induced ablation of peptidergic afferent terminals. Despite the suggested involvement of TRPV1 Ser801 phosphorylation on microtubule integrity, capsaicin-induced analgesia was not affected in TRPV1 S801A knock-in mice. In conclusion, capsaicin-induced depolymerization of axonal microtubules determined capsaicin-induced ablation of nociceptive terminals and the extent of analgesia. Further understanding of TRPV1/Ca 2+ -dependent mechanisms of capsaicin-induced ablation and analgesia may help to improve the management of chronic pain.
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Affiliation(s)
- Vipin Arora
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, the University of Maryland Baltimore, Baltimore, MD, United States
| | - Tingting Li
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, the University of Maryland Baltimore, Baltimore, MD, United States
| | - Sinu Kumari
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, the University of Maryland Baltimore, Baltimore, MD, United States
| | - Sheng Wang
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, the University of Maryland Baltimore, Baltimore, MD, United States
| | - Jamila Asgar
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, the University of Maryland Baltimore, Baltimore, MD, United States
| | - Man-Kyo Chung
- Department of Neural and Pain Sciences, School of Dentistry, Program in Neuroscience, Center to Advance Chronic Pain Research, the University of Maryland Baltimore, Baltimore, MD, United States
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8
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Partridge BR, Kani Y, Lorenzo MF, Campelo SN, Allen IC, Hinckley J, Hsu FC, Verbridge SS, Robertson JL, Davalos RV, Rossmeisl JH. High-Frequency Irreversible Electroporation (H-FIRE) Induced Blood-Brain Barrier Disruption Is Mediated by Cytoskeletal Remodeling and Changes in Tight Junction Protein Regulation. Biomedicines 2022; 10:1384. [PMID: 35740406 PMCID: PMC9220673 DOI: 10.3390/biomedicines10061384] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 06/07/2022] [Accepted: 06/09/2022] [Indexed: 12/25/2022] Open
Abstract
Glioblastoma is the deadliest malignant brain tumor. Its location behind the blood-brain barrier (BBB) presents a therapeutic challenge by preventing effective delivery of most chemotherapeutics. H-FIRE is a novel tumor ablation method that transiently disrupts the BBB through currently unknown mechanisms. We hypothesized that H-FIRE mediated BBB disruption (BBBD) occurs via cytoskeletal remodeling and alterations in tight junction (TJ) protein regulation. Intracranial H-FIRE was delivered to Fischer rats prior to sacrifice at 1-, 24-, 48-, 72-, and 96 h post-treatment. Cytoskeletal proteins and native and ubiquitinated TJ proteins (TJP) were evaluated using immunoprecipitation, Western blotting, and gene-expression arrays on treated and sham control brain lysates. Cytoskeletal and TJ protein expression were further evaluated with immunofluorescent microscopy. A decrease in the F/G-actin ratio, decreased TJP concentrations, and increased ubiquitination of TJP were observed 1-48 h post-H-FIRE compared to sham controls. By 72-96 h, cytoskeletal and TJP expression recovered to pretreatment levels, temporally corresponding with increased claudin-5 and zonula occludens-1 gene expression. Ingenuity pathway analysis revealed significant dysregulation of claudin genes, centered around claudin-6 in H-FIRE treated rats. In conclusion, H-FIRE is capable of permeating the BBB in a spatiotemporal manner via cytoskeletal-mediated TJP modulation. This minimally invasive technology presents with applications for localized and long-lived enhanced intracranial drug delivery.
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Affiliation(s)
- Brittanie R. Partridge
- Department of Small Animal Clinical Sciences, Virginia Tech, Blacksburg, VA 24061, USA; (B.R.P.); (Y.K.); (J.H.)
| | - Yukitaka Kani
- Department of Small Animal Clinical Sciences, Virginia Tech, Blacksburg, VA 24061, USA; (B.R.P.); (Y.K.); (J.H.)
| | - Melvin F. Lorenzo
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA; (M.F.L.); (S.N.C.)
| | - Sabrina N. Campelo
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA; (M.F.L.); (S.N.C.)
| | - Irving C. Allen
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Blacksburg, VA 24061, USA; (I.C.A.); (S.S.V.); (J.L.R.); (R.V.D.)
- Center of Engineered Health, Virginia Tech, Blacksburg, VA 24061, USA
| | - Jonathan Hinckley
- Department of Small Animal Clinical Sciences, Virginia Tech, Blacksburg, VA 24061, USA; (B.R.P.); (Y.K.); (J.H.)
| | - Fang-Chi Hsu
- Department of Biostatistics and Data Sciences, Division of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, NC 27101, USA;
| | - Scott S. Verbridge
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Blacksburg, VA 24061, USA; (I.C.A.); (S.S.V.); (J.L.R.); (R.V.D.)
- Center of Engineered Health, Virginia Tech, Blacksburg, VA 24061, USA
| | - John L. Robertson
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, Blacksburg, VA 24061, USA; (I.C.A.); (S.S.V.); (J.L.R.); (R.V.D.)
| | - Rafael V. Davalos
- Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA; (M.F.L.); (S.N.C.)
- Center of Engineered Health, Virginia Tech, Blacksburg, VA 24061, USA
| | - John H. Rossmeisl
- Department of Small Animal Clinical Sciences, Virginia Tech, Blacksburg, VA 24061, USA; (B.R.P.); (Y.K.); (J.H.)
- Center of Engineered Health, Virginia Tech, Blacksburg, VA 24061, USA
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9
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An Overview of Cell Membrane Perforation and Resealing Mechanisms for Localized Drug Delivery. Pharmaceutics 2022; 14:pharmaceutics14040886. [PMID: 35456718 PMCID: PMC9031838 DOI: 10.3390/pharmaceutics14040886] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 04/09/2022] [Accepted: 04/14/2022] [Indexed: 01/04/2023] Open
Abstract
Localized and reversible plasma membrane disruption is a promising technique employed for the targeted deposition of exogenous therapeutic compounds for the treatment of disease. Indeed, the plasma membrane represents a significant barrier to successful delivery, and various physical methods using light, sound, and electrical energy have been developed to generate cell membrane perforations to circumvent this issue. To restore homeostasis and preserve viability, localized cellular repair mechanisms are subsequently triggered to initiate a rapid restoration of plasma membrane integrity. Here, we summarize the known emergency membrane repair responses, detailing the salient membrane sealing proteins as well as the underlying cytoskeletal remodeling that follows the physical induction of a localized plasma membrane pore, and we present an overview of potential modulation strategies that may improve targeted drug delivery approaches.
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10
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Sachdev S, Potočnik T, Rems L, Miklavčič D. Revisiting the role of pulsed electric fields in overcoming the barriers to in vivo gene electrotransfer. Bioelectrochemistry 2022; 144:107994. [PMID: 34930678 DOI: 10.1016/j.bioelechem.2021.107994] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/15/2021] [Accepted: 11/02/2021] [Indexed: 12/21/2022]
Abstract
Gene therapies are revolutionizing medicine by providing a way to cure hitherto incurable diseases. The scientific and technological advances have enabled the first gene therapies to become clinically approved. In addition, with the ongoing COVID-19 pandemic, we are witnessing record speeds in the development and distribution of gene-based vaccines. For gene therapy to take effect, the therapeutic nucleic acids (RNA or DNA) need to overcome several barriers before they can execute their function of producing a protein or silencing a defective or overexpressing gene. This includes the barriers of the interstitium, the cell membrane, the cytoplasmic barriers and (in case of DNA) the nuclear envelope. Gene electrotransfer (GET), i.e., transfection by means of pulsed electric fields, is a non-viral technique that can overcome these barriers in a safe and effective manner. GET has reached the clinical stage of investigations where it is currently being evaluated for its therapeutic benefits across a wide variety of indications. In this review, we formalize our current understanding of GET from a biophysical perspective and critically discuss the mechanisms by which electric field can aid in overcoming the barriers. We also identify the gaps in knowledge that are hindering optimization of GET in vivo.
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Affiliation(s)
- Shaurya Sachdev
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Tjaša Potočnik
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Lea Rems
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia
| | - Damijan Miklavčič
- University of Ljubljana, Faculty of Electrical Engineering, Tržaška cesta 25, 1000 Ljubljana, Slovenia.
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11
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Shiota T, Nagata R, Kikuchi S, Nanaura H, Matsubayashi M, Nakanishi M, Kobashigawa S, Isozumi N, Kiriyama T, Nagayama K, Sugie K, Yamashiro Y, Mori E. C9orf72-Derived Proline:Arginine Poly-Dipeptides Modulate Cytoskeleton and Mechanical Stress Response. Front Cell Dev Biol 2022; 10:750829. [PMID: 35399536 PMCID: PMC8983821 DOI: 10.3389/fcell.2022.750829] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 03/07/2022] [Indexed: 11/28/2022] Open
Abstract
Proline:arginine (PR) poly-dipeptides from the GGGGCC repeat expansion in C9orf72 have cytotoxicity and bind intermediate filaments (IFs). However, it remains unknown how PR poly-dipeptides affect cytoskeletal organization and focal adhesion (FA) formation. Here, we show that changes to the cytoskeleton and FA by PR poly-dipeptides result in the alteration of cell stiffness and mechanical stress response. PR poly-dipeptides increased the junctions and branches of the IF network and increased cell stiffness. They also changed the distribution of actin filaments and increased the size of FA and intracellular calcium concentration. PR poly-dipeptides or an inhibitor of IF organization prevented cell detachment. Furthermore, PR poly-dipeptides induced upregulation of mechanical stress response factors and led to a maladaptive response to cyclic stretch. These results suggest that the effects of PR poly-dipeptides on mechanical properties and mechanical stress response may serve as a pathogenesis of C9orf72-related neurodegeneration.
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Affiliation(s)
- Tomo Shiota
- Department of Neurology, Nara Medical University, Kashihara, Japan
| | - Riko Nagata
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
| | - Sotaro Kikuchi
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
| | - Hitoki Nanaura
- Department of Neurology, Nara Medical University, Kashihara, Japan
| | - Masaya Matsubayashi
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
| | - Mari Nakanishi
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
| | - Shinko Kobashigawa
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
| | - Noriyoshi Isozumi
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
| | - Takao Kiriyama
- Department of Neurology, Nara Medical University, Kashihara, Japan
| | - Kazuaki Nagayama
- Micro-Nano Biomechanics Laboratory, Department of Mechanical Systems Engineering, Ibaraki University, Hitachi, Japan
| | - Kazuma Sugie
- Department of Neurology, Nara Medical University, Kashihara, Japan
| | - Yoshito Yamashiro
- Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance, Tsukuba, Japan
- *Correspondence: Yoshito Yamashiro, ; Eiichiro Mori,
| | - Eiichiro Mori
- Department of Future Basic Medicine, Nara Medical University, Kashihara, Japan
- V-iCliniX Laboratory, Nara Medical University, Kashihara, Japan
- *Correspondence: Yoshito Yamashiro, ; Eiichiro Mori,
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12
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Chambraud B, Byrne C, Meduri G, Baulieu EE, Giustiniani J. FKBP52 in Neuronal Signaling and Neurodegenerative Diseases: A Microtubule Story. Int J Mol Sci 2022; 23:ijms23031738. [PMID: 35163662 PMCID: PMC8836061 DOI: 10.3390/ijms23031738] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/24/2022] [Accepted: 01/28/2022] [Indexed: 02/06/2023] Open
Abstract
The FK506-binding protein 52 (FKBP52) belongs to a large family of ubiquitously expressed and highly conserved proteins (FKBPs) that share an FKBP domain and possess Peptidyl-Prolyl Isomerase (PPIase) activity. PPIase activity catalyzes the isomerization of Peptidyl-Prolyl bonds and therefore influences target protein folding and function. FKBP52 is particularly abundant in the nervous system and is partially associated with the microtubule network in different cell types suggesting its implication in microtubule function. Various studies have focused on FKBP52, highlighting its importance in several neuronal microtubule-dependent signaling pathways and its possible implication in neurodegenerative diseases such as tauopathies (i.e., Alzheimer disease) and alpha-synucleinopathies (i.e., Parkinson disease). This review summarizes our current understanding of FKBP52 actions in the microtubule environment, its implication in neuronal signaling and function, its interactions with other members of the FKBPs family and its involvement in neurodegenerative disease.
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Affiliation(s)
- Béatrice Chambraud
- INSERM U1195, Université Paris-Saclay, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France;
| | - Cillian Byrne
- Institut Professeur Baulieu, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France; (C.B.); (G.M.)
- Laboratoire des Biomolécules, LBM7203, CNRS, École Normale Supérieure, PSL University, Sorbonne Université, 75005 Paris, France
| | - Geri Meduri
- Institut Professeur Baulieu, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France; (C.B.); (G.M.)
| | - Etienne Emile Baulieu
- INSERM U1195, Université Paris-Saclay, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France;
- Institut Professeur Baulieu, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France; (C.B.); (G.M.)
- Correspondence: (E.E.B.); (J.G.); Tel.: +33-1-49-59-18-72 (J.G.); Fax: +33-1-49-59-92-03 (J.G.)
| | - Julien Giustiniani
- INSERM U1195, Université Paris-Saclay, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France;
- Institut Professeur Baulieu, 80 Rue du Général Leclerc, 94276 Kremlin-Bicêtre, France; (C.B.); (G.M.)
- Correspondence: (E.E.B.); (J.G.); Tel.: +33-1-49-59-18-72 (J.G.); Fax: +33-1-49-59-92-03 (J.G.)
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13
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Jenkins EPW, Finch A, Gerigk M, Triantis IF, Watts C, Malliaras GG. Electrotherapies for Glioblastoma. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2100978. [PMID: 34292672 PMCID: PMC8456216 DOI: 10.1002/advs.202100978] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/20/2021] [Indexed: 05/08/2023]
Abstract
Non-thermal, intermediate frequency (100-500 kHz) electrotherapies present a unique therapeutic strategy to treat malignant neoplasms. Here, pulsed electric fields (PEFs) which induce reversible or irreversible electroporation (IRE) and tumour-treating fields (TTFs) are reviewed highlighting the foundations, advances, and considerations of each method when applied to glioblastoma (GBM). Several biological aspects of GBM that contribute to treatment complexity (heterogeneity, recurrence, resistance, and blood-brain barrier(BBB)) and electrophysiological traits which are suggested to promote glioma progression are described. Particularly, the biological responses at the cellular and molecular level to specific parameters of the electrical stimuli are discussed offering ways to compare these parameters despite the lack of a universally adopted physical description. Reviewing the literature, a disconnect is found between electrotherapy techniques and how they target the biological complexities of GBM that make treatment difficult in the first place. An attempt is made to bridge the interdisciplinary gap by mapping biological characteristics to different methods of electrotherapy, suggesting important future research topics and directions in both understanding and treating GBM. To the authors' knowledge, this is the first paper that attempts an in-tandem assessment of the biological effects of different aspects of intermediate frequency electrotherapy methods, thus offering possible strategies toward GBM treatment.
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Affiliation(s)
- Elise P. W. Jenkins
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
| | - Alina Finch
- Institute of Cancer and Genomic ScienceUniversity of BirminghamBirminghamB15 2TTUK
| | - Magda Gerigk
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
| | - Iasonas F. Triantis
- Department of Electrical and Electronic EngineeringCity, University of LondonLondonEC1V 0HBUK
| | - Colin Watts
- Institute of Cancer and Genomic ScienceUniversity of BirminghamBirminghamB15 2TTUK
| | - George G. Malliaras
- Division of Electrical EngineeringDepartment of EngineeringUniversity of CambridgeCambridgeCB3 0FAUK
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14
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Zhao H, Wang L, Zeng K, Li J, Chen W, Liu YN. Nanomessenger-Mediated Signaling Cascade for Antitumor Immunotherapy. ACS NANO 2021; 15:13188-13199. [PMID: 34342966 DOI: 10.1021/acsnano.1c02765] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Chemical messengers have been recognized as signaling molecules involved in regulating various physiological and metabolic activities. Nevertheless, they usually show limited regulatory efficiency due to the complexity of biological processes. Especially for tumor cells, antideath pathways and tumor metastasis are readily activated to resist chemical messenger regulation, further impairing antitumor outcomes. Therefore, it is imperative to develop strategies for tumor eradication with chemical messengers. Herein, a nanomessenger was prepared with signaling transduction cascades to amplify the regulatory activity of chemical messengers and mediate antitumor immunotherapy. Ca2+ and H2S as two chemical messengers were released from nanomessengers to synergistically elevate intracellular Ca2+ stress and mediate subsequent cell death. Meanwhile, zinc protoporphyrin (ZnPP) as a messenger amplifier suppressed the antideath effect of tumor cells. As a result, tumor cells underwent Ca2+-dependent cell death via signaling transduction cascades to release tumor-associated antigens, which further served as an in situ tumor vaccine to activate antitumor immunity. In vivo studies revealed that both primary tumors and distant metastases were markedly eradicated. Furthermore, immunological memory was fabricated to arrest tumor metastasis and recurrence. This work introduces cascade engineering into chemical messengers and thus offers a strategy for amplifying chemical messenger-mediated cellular regulation, which would promote the future development of chemical messenger-mediated immunotherapy.̀.
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Affiliation(s)
- Henan Zhao
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science, College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - Liqiang Wang
- Henan Province Industrial Technology Research Institute of Resources and Materials, School of Material Science and Engineering, Zhengzhou University, Zhengzhou, Henan 450001, People's Republic of China
| | - Ke Zeng
- School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, People's Republic of China
| | - Jianghua Li
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science, College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - Wansong Chen
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science, College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - You-Nian Liu
- Hunan Provincial Key Laboratory of Micro & Nano Materials Interface Science, College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083, People's Republic of China
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15
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Myrka A, Buck L. Cytoskeletal Arrest: An Anoxia Tolerance Mechanism. Metabolites 2021; 11:metabo11080561. [PMID: 34436502 PMCID: PMC8401981 DOI: 10.3390/metabo11080561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/13/2021] [Accepted: 08/14/2021] [Indexed: 12/16/2022] Open
Abstract
Polymerization of actin filaments and microtubules constitutes a ubiquitous demand for cellular adenosine-5′-triphosphate (ATP) and guanosine-5′-triphosphate (GTP). In anoxia-tolerant animals, ATP consumption is minimized during overwintering conditions, but little is known about the role of cell structure in anoxia tolerance. Studies of overwintering mammals have revealed that microtubule stability in neurites is reduced at low temperature, resulting in withdrawal of neurites and reduced abundance of excitatory synapses. Literature for turtles is consistent with a similar downregulation of peripheral cytoskeletal activity in brain and liver during anoxic overwintering. Downregulation of actin dynamics, as well as modification to microtubule organization, may play vital roles in facilitating anoxia tolerance. Mitochondrial calcium release occurs during anoxia in turtle neurons, and subsequent activation of calcium-binding proteins likely regulates cytoskeletal stability. Production of reactive oxygen species (ROS) formation can lead to catastrophic cytoskeletal damage during overwintering and ROS production can be regulated by the dynamics of mitochondrial interconnectivity. Therefore, suppression of ROS formation is likely an important aspect of cytoskeletal arrest. Furthermore, gasotransmitters can regulate ROS levels, as well as cytoskeletal contractility and rearrangement. In this review we will explore the energetic costs of cytoskeletal activity, the cellular mechanisms regulating it, and the potential for cytoskeletal arrest being an important mechanism permitting long-term anoxia survival in anoxia-tolerant species, such as the western painted turtle and goldfish.
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Affiliation(s)
- Alexander Myrka
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada;
| | - Leslie Buck
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5S 3G5, Canada;
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON M5S 3G5, Canada
- Correspondence: ; Tel.: +1-416-978-3506
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16
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Han SJ, Noh M, Jang J, Lee JB, Kim KS. Electric fields regulate cellular elasticity through intracellular Ca 2+ concentrations. J Cell Physiol 2021; 236:7450-7463. [PMID: 33993476 DOI: 10.1002/jcp.30417] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 04/25/2021] [Accepted: 04/28/2021] [Indexed: 11/06/2022]
Abstract
Cellular elasticity is a key factor related to a broad range of physiological and pathological processes. The elasticity of a single cell has thus emerged as a potential biomarker to characterize the cellular state. Both internal and external stimuli affect cellular elasticity, and changes in elasticity can cause alterations in cellular characteristics or function. The application of electric fields (EFs) is a promising method that can be used to change cellular elasticity; however, the mechanisms underlying its effect remain unknown. Here, we demonstrate EFs-induced elasticity changes in human dermal fibroblasts and discuss the underlying mechanism related to actin polymerization. Cellular elasticity increases after EF (50 mV/mm) stimulation, reaching a maximum at 30 min before decreasing between 30 and 120 min. The cellular elasticity under EF stimulation, regardless of stimulation time, is higher than that of the control. F-actin regulates the elasticity of cells through gelsolin activation. We show changes in intracellular Ca2+ caused by EFs, which induced gelsolin activation and F-actin content changes. This result demonstrates a series of processes in which external electrical stimulation conditions regulate cellular elasticity.
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Affiliation(s)
- Se Jik Han
- Department of Biomedical Engineering, Graduate School, Kyung Hee University, Seoul, Korea.,Department of Biomedical Engineering, Kyung Hee University, Seoul, Korea
| | - Minjoo Noh
- Innovation Lab, Department of Innovation, Cosmax R&I Center, Gyeonggi do, Korea
| | - Jihui Jang
- Innovation Lab, Department of Innovation, Cosmax R&I Center, Gyeonggi do, Korea
| | - Jun Bae Lee
- Innovation Lab, Department of Innovation, Cosmax R&I Center, Gyeonggi do, Korea
| | - Kyung Sook Kim
- Department of Biomedical Engineering, Kyung Hee University, Seoul, Korea
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17
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Peng Z, Resnick A, Young YN. Primary cilium: a paradigm for integrating mathematical modeling with experiments and numerical simulations in mechanobiology. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2021; 18:1215-1237. [PMID: 33757184 PMCID: PMC8552149 DOI: 10.3934/mbe.2021066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Primary cilia are non-motile, solitary (one per cell) microtubule-based organelles that emerge from the mother centriole after cells have exited the mitotic cycle. Identified as a mechanosensing organelle that responds to both mechanical and chemical stimuli, the primary cilium provides a fertile ground for integrative investigations of mathematical modeling, numerical simulations, and experiments. Recent experimental findings revealed considerable complexity to the underlying mechanosensory mechanisms that transmit extracellular stimuli to intracellular signaling many of which include primary cilia. In this invited review, we provide a brief survey of experimental findings on primary cilia and how these results lead to various mathematical models of the mechanics of the primary cilium bent under an external forcing such as a fluid flow or a trap. Mathematical modeling of the primary cilium as a fluid-structure interaction problem highlights the importance of basal anchorage and the anisotropic moduli of the microtubules. As theoretical modeling and numerical simulations progress, along with improved state-of-the-art experiments on primary cilia, we hope that details of ciliary regulated mechano-chemical signaling dynamics in cellular physiology will be understood in the near future.
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Affiliation(s)
- Zhangli Peng
- Department of Bioengineering, University of Illinois at Chicago, 851 S. Morgan St., Chicago, IL 60607, USA
| | - Andrew Resnick
- Department of Physics, Center for Gene Regulation in Health and Disease, Cleveland State University, Cleveland, OH 44115, USA
| | - Y.-N. Young
- Department of Mathematical Sciences, New Jersey Institute of Technology, University Heights, Newark, NJ 07102, USA
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18
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Kalra AP, Eakins BB, Patel SD, Ciniero G, Rezania V, Shankar K, Tuszynski JA. All Wired Up: An Exploration of the Electrical Properties of Microtubules and Tubulin. ACS NANO 2020; 14:16301-16320. [PMID: 33213135 DOI: 10.1021/acsnano.0c06945] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Microtubules are hollow, cylindrical polymers of the protein α, β tubulin, that interact mechanochemically with a variety of macromolecules. Due to their mechanically robust nature, microtubules have gained attention as tracks for precisely directed transport of nanomaterials within lab-on-a-chip devices. Primarily due to the unusually negative tail-like C-termini of tubulin, recent work demonstrates that these biopolymers are also involved in a broad spectrum of intracellular electrical signaling. Microtubules and their electrostatic properties are discussed in this Review, followed by an evaluation of how these biopolymers respond mechanically to electrical stimuli, through microtubule migration, electrorotation and C-termini conformation changes. Literature focusing on how microtubules act as nanowires capable of intracellular ionic transport, charge storage, and ionic signal amplification is reviewed, illustrating how these biopolymers attenuate ionic movement in response to electrical stimuli. The Review ends with a discussion on the important questions, challenges, and future opportunities for intracellular microtubule-based electrical signaling.
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Affiliation(s)
- Aarat P Kalra
- Department of Physics, University of Alberta, 11335 Saskatchewan Dr NW, Edmonton, Alberta T6G 2M9, Canada
| | - Boden B Eakins
- Department of Electrical and Computer Engineering, University of Alberta, 9107-116 St, Edmonton, Alberta T6G 2 V4, Canada
| | - Sahil D Patel
- Department of Electrical and Computer Engineering, University of Alberta, 9107-116 St, Edmonton, Alberta T6G 2 V4, Canada
| | - Gloria Ciniero
- Department of Mechanical and Aerospace Engineering (DIMEAS), Politecnico di Torino, Torino 10129, Italy
| | - Vahid Rezania
- Department of Physical Sciences, MacEwan University, Edmonton, Alberta T5J 4S2, Canada
| | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, 9107-116 St, Edmonton, Alberta T6G 2 V4, Canada
| | - Jack A Tuszynski
- Department of Physics, University of Alberta, 11335 Saskatchewan Dr NW, Edmonton, Alberta T6G 2M9, Canada
- Department of Mechanical and Aerospace Engineering (DIMEAS), Politecnico di Torino, Torino 10129, Italy
- Department of Oncology, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
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19
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Fight fire with fire: Neurobiology of capsaicin-induced analgesia for chronic pain. Pharmacol Ther 2020; 220:107743. [PMID: 33181192 DOI: 10.1016/j.pharmthera.2020.107743] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 11/04/2020] [Indexed: 12/12/2022]
Abstract
Capsaicin, the pungent ingredient in chili peppers, produces intense burning pain in humans. Capsaicin selectively activates the transient receptor potential vanilloid 1 (TRPV1), which is enriched in nociceptive primary afferents, and underpins the mechanism for capsaicin-induced burning pain. Paradoxically, capsaicin has long been used as an analgesic. The development of topical patches and injectable formulations containing capsaicin has led to application in clinical settings to treat chronic pain conditions, such as neuropathic pain and the potential to treat osteoarthritis. More detailed determination of the neurobiological mechanisms of capsaicin-induced analgesia should provide the logical rationale for capsaicin therapy and help to overcome the treatment's limitations, which include individual differences in treatment outcome and procedural discomfort. Low concentrations of capsaicin induce short-term defunctionalization of nociceptor terminals. This phenomenon is reversible within hours and, hence, likely does not account for the clinical benefit. By contrast, high concentrations of capsaicin lead to long-term defunctionalization mediated by the ablation of TRPV1-expressing afferent terminals, resulting in long-lasting analgesia persisting for several months. Recent studies have shown that capsaicin-induced Ca2+/calpain-mediated ablation of axonal terminals is necessary to produce long-lasting analgesia in a mouse model of neuropathic pain. In combination with calpain, axonal mitochondrial dysfunction and microtubule disorganization may also contribute to the longer-term effects of capsaicin. The analgesic effects subside over time in association with the regeneration of the ablated afferent terminals. Further determination of the neurobiological mechanisms of capsaicin-induced analgesia should lead to more efficacious non-opioidergic analgesic options with fewer adverse side effects.
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20
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Ho KH, Yang X, Osipovich AB, Cabrera O, Hayashi ML, Magnuson MA, Gu G, Kaverina I. Glucose Regulates Microtubule Disassembly and the Dose of Insulin Secretion via Tau Phosphorylation. Diabetes 2020; 69:1936-1947. [PMID: 32540877 PMCID: PMC7458041 DOI: 10.2337/db19-1186] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 06/07/2020] [Indexed: 12/16/2022]
Abstract
The microtubule cytoskeleton of pancreatic islet β-cells regulates glucose-stimulated insulin secretion (GSIS). We have reported that the microtubule-mediated movement of insulin vesicles away from the plasma membrane limits insulin secretion. High glucose-induced remodeling of microtubule network facilitates robust GSIS. This remodeling involves disassembly of old microtubules and nucleation of new microtubules. Here, we examine the mechanisms whereby glucose stimulation decreases microtubule lifetimes in β-cells. Using real-time imaging of photoconverted microtubules, we demonstrate that high levels of glucose induce rapid microtubule disassembly preferentially in the periphery of individual β-cells, and this process is mediated by the phosphorylation of microtubule-associated protein tau. Specifically, high glucose induces tau hyper-phosphorylation via glucose-responsive kinases GSK3, PKA, PKC, and CDK5. This causes dissociation of tau from and subsequent destabilization of microtubules. Consequently, tau knockdown in mouse islet β-cells facilitates microtubule turnover, causing increased basal insulin secretion, depleting insulin vesicles from the cytoplasm, and impairing GSIS. More importantly, tau knockdown uncouples microtubule destabilization from glucose stimulation. These findings suggest that tau suppresses peripheral microtubules turning over to restrict insulin oversecretion in basal conditions and preserve the insulin pool that can be released following stimulation; high glucose promotes tau phosphorylation to enhance microtubule disassembly to acutely enhance GSIS.
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Affiliation(s)
- Kung-Hsien Ho
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
- Program of Developmental Biology and Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
| | - Xiaodun Yang
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
- Program of Developmental Biology and Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
| | - Anna B Osipovich
- Program of Developmental Biology and Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | | | | | - Mark A Magnuson
- Program of Developmental Biology and Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN
| | - Guoqiang Gu
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
- Program of Developmental Biology and Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
| | - Irina Kaverina
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN
- Program of Developmental Biology and Vanderbilt Center for Stem Cell Biology, Vanderbilt University, Nashville, TN
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21
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Tubulin islands containing slowly hydrolyzable GTP analogs regulate the mechanism and kinetics of microtubule depolymerization. Sci Rep 2020; 10:13661. [PMID: 32788644 PMCID: PMC7423891 DOI: 10.1038/s41598-020-70602-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 05/22/2020] [Indexed: 01/05/2023] Open
Abstract
Dynamic instability of microtubules is characterized by stochastically alternating phases of growth and shrinkage and is hypothesized to be controlled by the conformation and nucleotide state of tubulin dimers within the microtubule lattice. Specifically, conformation changes (compression) in the tubulin dimer following the hydrolysis of GTP have been suggested to generate stress and drive depolymerization. In the present study, molecular dynamics simulations were used in tandem with in vitro experiments to investigate changes in depolymerization based on the presence of islands of uncompressed (GMPCPP) dimers in the microtubule lattice. Both methods revealed an exponential decay in the kinetic rate of depolymerization corresponding to the relative level of uncompressed (GMPCPP) dimers, beginning at approximately 20% incorporation. This slowdown was accompanied by a distinct morphological change from unpeeling "ram's horns" to blunt-ended dissociation at the microtubule end. Collectively these data demonstrated that islands of uncompressed dimers can alter the mechanism and kinetics of depolymerization in a manner consistent with promoting rescue events.
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22
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Ohto-Fujita E, Hayasaki S, Atomi A, Fujiki S, Watanabe T, Boelens WC, Shimizu M, Atomi Y. Dynamic localization of αB-crystallin at the microtubule cytoskeleton network in beating heart cells. J Biochem 2020; 168:125-137. [PMID: 32725133 DOI: 10.1093/jb/mvaa025] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 02/05/2020] [Indexed: 01/17/2023] Open
Abstract
αB-crystallin is highly expressed in the heart and slow skeletal muscle; however, the roles of αB-crystallin in the muscle are obscure. Previously, we showed that αB-crystallin localizes at the sarcomere Z-bands, corresponding to the focal adhesions of cultured cells. In myoblast cells, αB-crystallin completely colocalizes with microtubules and maintains cell shape and adhesion. In this study, we show that in beating cardiomyocytes α-tubulin and αB-crystallin colocalize at the I- and Z-bands of the myocardium, where it may function as a molecular chaperone for tubulin/microtubules. Fluorescence recovery after photobleaching (FRAP) analysis revealed that the striated patterns of GFP-αB-crystallin fluorescence recovered quickly at 37°C. FRAP mobility assay also showed αB-crystallin to be associated with nocodazole-treated free tubulin dimers but not with taxol-treated microtubules. The interaction of αB-crystallin and free tubulin was further confirmed by immunoprecipitation and microtubule sedimentation assay in the presence of 1-100 μM calcium, which destabilizes microtubules. Förster resonance energy transfer analysis showed that αB-crystallin and tubulin were at 1-10 nm apart from each other in the presence of colchicine. These results suggested that αB-crystallin may play an essential role in microtubule dynamics by maintaining free tubulin in striated muscles, such as the soleus or cardiac muscles.
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Affiliation(s)
- Eri Ohto-Fujita
- Material Health Science Laboratory, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Saaya Hayasaki
- Material Health Science Laboratory, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Aya Atomi
- Material Health Science Laboratory, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Soichiro Fujiki
- Department of Physiology and Biological Information, Dokkyo Medical University, Mibu, Tochigi 321-0293, Japan
| | - Toshiyuki Watanabe
- Division of Applied Chemistry, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Wilbert C Boelens
- Department of Biomolecular Chemistry, Institute for Molecules and Materials (IMM), Radboud University, Nijmegen, The Netherlands
| | - Miho Shimizu
- Material Health Science Laboratory, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
| | - Yoriko Atomi
- Material Health Science Laboratory, Graduate School of Engineering, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
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23
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Chafai DE, Vostárek F, Dráberová E, Havelka D, Arnaud-Cormos D, Leveque P, Janáček J, Kubínová L, Cifra M, Dráber P. Microtubule Cytoskeleton Remodeling by Nanosecond Pulsed Electric Fields. ACTA ACUST UNITED AC 2020; 4:e2000070. [PMID: 32459064 DOI: 10.1002/adbi.202000070] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/04/2020] [Indexed: 12/15/2022]
Abstract
Remodeling of nanoscopic structures is not just crucial for cell biology, but it is also at the core of bioinspired materials. While the microtubule cytoskeleton in cells undergoes fast adaptation, adaptive materials still face this remodeling challenge. Moreover, the guided reorganization of the microtubule network and the correction of its abnormalities is still a major aim. This work reports new findings for externally triggered microtubule network remodeling by nanosecond electropulses (nsEPs). At first, a wide range of nsEP parameters, applied in a low conductivity buffer, is explored to find out the minimal nsEP dosage needed to disturb microtubules in various cell types. The time course of apoptosis and microtubule recovery in the culture medium is thereafter assessed. Application of nsEPs to cells in culture media result in modulation of microtubule binding properties to end-binding (EB1) protein, quantified by newly developed image processing techniques. The microtubules in nsEP-treated cells in the culture medium have longer EB1 comets but their density is lower than that of the control. The nsEP treatment represents a strategy for microtubule remodeling-based nano-biotechnological applications, such as engineering of self-healing materials, and as a manipulation tool for the evaluation of microtubule remodeling mechanisms during various biological processes in health and disease.
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Affiliation(s)
- Djamel Eddine Chafai
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 182 51, Czechia
| | - František Vostárek
- Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 142 20, Czechia
| | - Eduarda Dráberová
- Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 142 20, Czechia
| | - Daniel Havelka
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 182 51, Czechia
| | - Delia Arnaud-Cormos
- University of Limoges, CNRS, XLIM, UMR 7252, Limoges, F-87000, France.,Institut Universitaire de France (IUF), Paris, F-75005, France
| | - Philippe Leveque
- University of Limoges, CNRS, XLIM, UMR 7252, Limoges, F-87000, France
| | - Jiří Janáček
- Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 142 20, Czechia
| | - Lucie Kubínová
- Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, Prague, 142 20, Czechia
| | - Michal Cifra
- Institute of Photonics and Electronics of the Czech Academy of Sciences, Chaberská 1014/57, Prague, 182 51, Czechia
| | - Pavel Dráber
- Institute of Molecular Genetics of the Czech Academy of Sciences, Vídeňská 1083, Prague, 142 20, Czechia
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Graybill PM, Davalos RV. Cytoskeletal Disruption after Electroporation and Its Significance to Pulsed Electric Field Therapies. Cancers (Basel) 2020; 12:E1132. [PMID: 32366043 PMCID: PMC7281591 DOI: 10.3390/cancers12051132] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/18/2022] Open
Abstract
Pulsed electric fields (PEFs) have become clinically important through the success of Irreversible Electroporation (IRE), Electrochemotherapy (ECT), and nanosecond PEFs (nsPEFs) for the treatment of tumors. PEFs increase the permeability of cell membranes, a phenomenon known as electroporation. In addition to well-known membrane effects, PEFs can cause profound cytoskeletal disruption. In this review, we summarize the current understanding of cytoskeletal disruption after PEFs. Compiling available studies, we describe PEF-induced cytoskeletal disruption and possible mechanisms of disruption. Additionally, we consider how cytoskeletal alterations contribute to cell-cell and cell-substrate disruption. We conclude with a discussion of cytoskeletal disruption-induced anti-vascular effects of PEFs and consider how a better understanding of cytoskeletal disruption after PEFs may lead to more effective therapies.
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Affiliation(s)
- Philip M. Graybill
- BEMS Lab, Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA;
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061, USA
| | - Rafael V. Davalos
- BEMS Lab, Department of Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, VA 24061, USA;
- Department of Mechanical Engineering, Virginia Tech, Blacksburg, VA 24061, USA
- Virginia Tech–Wake Forest University, School of Biomedical Engineering and Sciences, Blacksburg, VA 24061, USA
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25
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NETosis proceeds by cytoskeleton and endomembrane disassembly and PAD4-mediated chromatin decondensation and nuclear envelope rupture. Proc Natl Acad Sci U S A 2020; 117:7326-7337. [PMID: 32170015 PMCID: PMC7132277 DOI: 10.1073/pnas.1909546117] [Citation(s) in RCA: 208] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Neutrophils are white blood cells specialized as the first line of host defense in the immune system. One way they protect organisms is through NETosis, in which they expel their DNA to form a web-like trap that ensnares pathogens and promotes clotting. However, NETs also mediate sterile inflammation, causing damage to the body. We used high-resolution live-cell microscopy to characterize the timing of dynamic cellular events leading to NETosis in human and mouse neutrophils and a neutrophil-like cell line. We discovered that NETosis proceeds by a stepwise sequence of cellular events that is conserved across species and requires the activity of the PAD4 enzyme for DNA to be released from the nucleus and cell membrane. Neutrophil extracellular traps (NETs) are web-like DNA structures decorated with histones and cytotoxic proteins that are released by activated neutrophils to trap and neutralize pathogens during the innate immune response, but also form in and exacerbate sterile inflammation. Peptidylarginine deiminase 4 (PAD4) citrullinates histones and is required for NET formation (NETosis) in mouse neutrophils. While the in vivo impact of NETs is accumulating, the cellular events driving NETosis and the role of PAD4 in these events are unclear. We performed high-resolution time-lapse microscopy of mouse and human neutrophils and differentiated HL-60 neutrophil-like cells (dHL-60) labeled with fluorescent markers of organelles and stimulated with bacterial toxins or Candida albicans to induce NETosis. Upon stimulation, cells exhibited rapid disassembly of the actin cytoskeleton, followed by shedding of plasma membrane microvesicles, disassembly and remodeling of the microtubule and vimentin cytoskeletons, ER vesiculation, chromatin decondensation and nuclear rounding, progressive plasma membrane and nuclear envelope (NE) permeabilization, nuclear lamin meshwork and then NE rupture to release DNA into the cytoplasm, and finally plasma membrane rupture and discharge of extracellular DNA. Inhibition of actin disassembly blocked NET release. Mouse and dHL-60 cells bearing genetic alteration of PAD4 showed that chromatin decondensation, lamin meshwork and NE rupture and extracellular DNA release required the enzymatic and nuclear localization activities of PAD4. Thus, NETosis proceeds by a stepwise sequence of cellular events culminating in the PAD4-mediated expulsion of DNA.
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Warren JD, Orr B, Compton DA. A comparative analysis of methods to measure kinetochore-microtubule attachment stability. Methods Cell Biol 2020; 158:91-116. [PMID: 32423652 PMCID: PMC7727308 DOI: 10.1016/bs.mcb.2020.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
During mitosis, spindle microtubules dynamically attach to and detach from kinetochores in a precise and regulated fashion. To ensure mitotic fidelity, kinetochore-microtubule (k-MT) attachments must be stable enough to satisfy the spindle assembly checkpoint (SAC), but sufficiently unstable to facilitate the correction of maloriented attachments. Different methods are available to assess k-MT stability in both live and fixed cells, but a comparative survey of these methods has not yet been reported. Here, we evaluate several quantitative and semiquantitative methods for determining k-MT stability and apply each technique to illustrate changes in spindle microtubule dynamics upon perturbation with physiologically relevant concentrations of microtubule stabilizing (Taxol) and destabilizing (UMK57 and nocodazole) compounds. We discuss the utility of each technique for defining specific features of spindle microtubule dynamics and k-MT attachment stability.
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Affiliation(s)
- Jessica D Warren
- Department of Biochemistry and Cell Biology, Geisel School of Medicine, Hanover, NH, United States; Norris Cotton Cancer Center, Lebanon, NH, United States
| | - Bernardo Orr
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal; i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Duane A Compton
- Department of Biochemistry and Cell Biology, Geisel School of Medicine, Hanover, NH, United States; Norris Cotton Cancer Center, Lebanon, NH, United States.
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Tian N, Hanson KA, Canty AJ, Vickers JC, King AE. Microtubule‐dependent processes precede pathological calcium influx in excitotoxin‐induced axon degeneration. J Neurochem 2019; 152:542-555. [DOI: 10.1111/jnc.14909] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 10/02/2019] [Accepted: 10/31/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Nan Tian
- Wicking Dementia Research and Education Centre University of Tasmania Hobart Tasmania Australia
| | - Kelsey A. Hanson
- Wicking Dementia Research and Education Centre University of Tasmania Hobart Tasmania Australia
| | - Alison J. Canty
- Wicking Dementia Research and Education Centre University of Tasmania Hobart Tasmania Australia
| | - James C. Vickers
- Wicking Dementia Research and Education Centre University of Tasmania Hobart Tasmania Australia
| | - Anna E. King
- Wicking Dementia Research and Education Centre University of Tasmania Hobart Tasmania Australia
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28
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Hahn I, Voelzmann A, Liew YT, Costa-Gomes B, Prokop A. The model of local axon homeostasis - explaining the role and regulation of microtubule bundles in axon maintenance and pathology. Neural Dev 2019; 14:11. [PMID: 31706327 PMCID: PMC6842214 DOI: 10.1186/s13064-019-0134-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Accepted: 10/02/2019] [Indexed: 12/20/2022] Open
Abstract
Axons are the slender, cable-like, up to meter-long projections of neurons that electrically wire our brains and bodies. In spite of their challenging morphology, they usually need to be maintained for an organism's lifetime. This makes them key lesion sites in pathological processes of ageing, injury and neurodegeneration. The morphology and physiology of axons crucially depends on the parallel bundles of microtubules (MTs), running all along to serve as their structural backbones and highways for life-sustaining cargo transport and organelle dynamics. Understanding how these bundles are formed and then maintained will provide important explanations for axon biology and pathology. Currently, much is known about MTs and the proteins that bind and regulate them, but very little about how these factors functionally integrate to regulate axon biology. As an attempt to bridge between molecular mechanisms and their cellular relevance, we explain here the model of local axon homeostasis, based on our own experiments in Drosophila and published data primarily from vertebrates/mammals as well as C. elegans. The model proposes that (1) the physical forces imposed by motor protein-driven transport and dynamics in the confined axonal space, are a life-sustaining necessity, but pose a strong bias for MT bundles to become disorganised. (2) To counterbalance this risk, MT-binding and -regulating proteins of different classes work together to maintain and protect MT bundles as necessary transport highways. Loss of balance between these two fundamental processes can explain the development of axonopathies, in particular those linking to MT-regulating proteins, motors and transport defects. With this perspective in mind, we hope that more researchers incorporate MTs into their work, thus enhancing our chances of deciphering the complex regulatory networks that underpin axon biology and pathology.
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Affiliation(s)
- Ines Hahn
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - André Voelzmann
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - Yu-Ting Liew
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - Beatriz Costa-Gomes
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK
| | - Andreas Prokop
- Manchester Academic Health Science Centre, Faculty of Biology, Medicine and Health, The University of Manchester, School of Biology, Manchester, UK.
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29
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Signaling pathways involved in adaptive responses to cell membrane disruption. CURRENT TOPICS IN MEMBRANES 2019; 84:99-127. [PMID: 31610867 DOI: 10.1016/bs.ctm.2019.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Plasma membrane disruption occurs frequently in many animal tissues. Cell membrane disruption induces not only a rapid and massive influx of Ca2+ into the cytosol but also an efflux or release of various signaling molecules, such as ATP, from the cytosol; in turn, these signaling molecules stimulate a variety of pathways in both wounded and non-wounded neighboring cells. These signals first trigger cell membrane repair responses in the wounded cell but then induce an adaptive response, which results in faster membrane repair in the event of future wounds in both wounded and non-wounded neighboring cells. In addition, signaling pathways stimulated by membrane disruption induce other adaptive responses, including cell survival, regeneration, migration, and proliferation. This chapter summarizes the role of intra- and intercellular signaling pathways in adaptive responses triggered by cell membrane disruption.
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30
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Mirvis M, Siemers KA, Nelson WJ, Stearns TP. Primary cilium loss in mammalian cells occurs predominantly by whole-cilium shedding. PLoS Biol 2019; 17:e3000381. [PMID: 31314751 PMCID: PMC6699714 DOI: 10.1371/journal.pbio.3000381] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 08/19/2019] [Accepted: 07/02/2019] [Indexed: 12/17/2022] Open
Abstract
The primary cilium is a central signaling hub in cell proliferation and differentiation and is built and disassembled every cell cycle in many animal cells. Disassembly is critically important, as misregulation or delay of cilia loss leads to cell cycle defects. The physical means by which cilia are lost are poorly understood but are thought to involve resorption of ciliary components into the cell body. To investigate cilium loss in mammalian cells, we used live-cell imaging to comprehensively characterize individual events. The predominant mode of cilium loss was rapid deciliation, in which the membrane and axoneme of the cilium was shed from the cell. Gradual resorption was also observed, as well as events in which a period of gradual resorption was followed by rapid deciliation. Deciliation resulted in intact shed cilia that could be recovered from culture medium and contained both membrane and axoneme proteins. We modulated levels of katanin and intracellular calcium, two putative regulators of deciliation, and found that excess katanin promotes cilia loss by deciliation, independently of calcium. Together, these results suggest that mammalian ciliary loss involves a tunable decision between deciliation and resorption.
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Affiliation(s)
- Mary Mirvis
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
| | - Kathleen A. Siemers
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - W. James Nelson
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California, United States of America
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Tim P. Stearns
- Department of Biology, Stanford University, Stanford, California, United States of America
- Department of Genetics, Stanford University, Stanford, California, United States of America
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31
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Hansen M, Thrane C, Olsson S, Sørensen J. Confocal imaging of living fungal hyphae challenged with the fungal antagonist viscosinamide. Mycologia 2019. [DOI: 10.1080/00275514.2000.12061147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Michael Hansen
- Section of Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C (Copenhagen), Denmark
| | - Charlotte Thrane
- Section of Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C (Copenhagen), Denmark
| | - Stefan Olsson
- Section of Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C (Copenhagen), Denmark
| | - Jan Sørensen
- Section of Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C (Copenhagen), Denmark
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32
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Brito C, Cabanes D, Sarmento Mesquita F, Sousa S. Mechanisms protecting host cells against bacterial pore-forming toxins. Cell Mol Life Sci 2019; 76:1319-1339. [PMID: 30591958 PMCID: PMC6420883 DOI: 10.1007/s00018-018-2992-8] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 12/19/2022]
Abstract
Pore-forming toxins (PFTs) are key virulence determinants produced and secreted by a variety of human bacterial pathogens. They disrupt the plasma membrane (PM) by generating stable protein pores, which allow uncontrolled exchanges between the extracellular and intracellular milieus, dramatically disturbing cellular homeostasis. In recent years, many advances were made regarding the characterization of conserved repair mechanisms that allow eukaryotic cells to recover from mechanical disruption of the PM membrane. However, the specificities of the cell recovery pathways that protect host cells against PFT-induced damage remain remarkably elusive. During bacterial infections, the coordinated action of such cell recovery processes defines the outcome of infected cells and is, thus, critical for our understanding of bacterial pathogenesis. Here, we review the cellular pathways reported to be involved in the response to bacterial PFTs and discuss their impact in single-cell recovery and infection.
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Affiliation(s)
- Cláudia Brito
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Didier Cabanes
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal
| | - Francisco Sarmento Mesquita
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
- Global Health Institute, School of Life Science, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
| | - Sandra Sousa
- i3S-Instituto de Investigação e Inovação em Saúde, IBMC, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135, Porto, Portugal.
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33
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Fees CP, Moore JK. A unified model for microtubule rescue. Mol Biol Cell 2019; 30:753-765. [PMID: 30672721 PMCID: PMC6589779 DOI: 10.1091/mbc.e18-08-0541] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 12/06/2018] [Accepted: 01/17/2019] [Indexed: 11/23/2022] Open
Abstract
How microtubules transition from depolymerization to polymerization, known as rescue, is poorly understood. Here we examine two models for rescue: 1) an "end-driven" model in which the depolymerizing end stochastically switches to a stable state; and 2) a "lattice-driven" model in which rescue sites are integrated into the microtubule before depolymerization. We test these models using a combination of computational simulations and in vitro experiments with purified tubulin. Our findings support the "lattice-driven" model by identifying repeated rescue sites in microtubules. In addition, we discover an important role for divalent cations in determining the frequency and location of rescue sites. We use "wash-in" experiments to show that divalent cations inhibit rescue during depolymerization, but not during polymerization. We propose a unified model in which rescues are driven by embedded rescue sites in microtubules, but the activity of these sites is influenced by changes in the depolymerizing ends.
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Affiliation(s)
- Colby P. Fees
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Jeffrey K. Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
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Goto T, Kanda K, Nishikata T. Non-centrosomal microtubule structures regulated by egg activation signaling contribute to cytoplasmic and cortical reorganization in the ascidian egg. Dev Biol 2018; 448:161-172. [PMID: 31030741 DOI: 10.1016/j.ydbio.2018.10.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 10/10/2018] [Accepted: 10/17/2018] [Indexed: 10/28/2022]
Abstract
In the first ascidian cell cycle, cytoplasmic and cortical reorganization is required for distributing maternal factors to their appropriate positions, resulting in the formation of the embryonic axis. This cytoplasmic reorganization is considered to depend on the cortical microfilament network in the first phase and on the sperm astral microtubule (MT) in the second phase. Recently, we described three novel MT structures: a deeply extended MT meshwork (DEM) in the entire subcortical region of the unfertilized egg, transiently accumulated MT fragments (TAF) in the vegetal pole, and a cortical MT array in the posterior vegetal cortex (CAMP). Particularly, our previous study showed CAMP to contribute to the movement of myoplasm. In addition, it is very similar to the parallel MT array, which appears during cortical rotation in Xenopus eggs. However, how these MT structures are organized is still unclear. Here, we investigated the relationship between the egg activation pathway and MT structures during the first ascidian cell cycle. First, we carefully analyzed cell cycle progression through meiosis I and II and the first mitosis, and successfully established a standard time table of cell cycle events. Using this time table as a reference, we precisely described the behavior of novel MT structures and revealed that it was closely correlated with cell cycle events. Moreover, pharmacological experiments supported the relationship between these MT structures and the signal transduction mechanisms that begin after fertilization, including Ca2+ signaling, MPF signaling, and MEK/MAPK signaling. Especially, CAMP formation was directed by activities of cyclin-dependent kinases. As these MT structures are conserved, at least, within chordate group, we emphasize the importance of understanding the controlling mechanisms of MT dynamics, which is important for embryonic axis determination in the ascidian egg.
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Affiliation(s)
- Toshiyuki Goto
- Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe, Hyogo 650-0047, Japan
| | - Kazumasa Kanda
- Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe, Hyogo 650-0047, Japan
| | - Takahito Nishikata
- Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, Kobe, Hyogo 650-0047, Japan.
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35
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Moskalensky AE, Litvinenko AL. The platelet shape change: biophysical basis and physiological consequences. Platelets 2018; 30:543-548. [DOI: 10.1080/09537104.2018.1514109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Alexander E. Moskalensky
- Laboratory of Optics and Dynamics of Biological Systems, Novosibirsk State University, Novosibirsk, Russia
- Laboratory of Cytometry and Biokinetics, Voevodsky Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia
| | - Alena L. Litvinenko
- Laboratory of Optics and Dynamics of Biological Systems, Novosibirsk State University, Novosibirsk, Russia
- Laboratory of Cytometry and Biokinetics, Voevodsky Institute of Chemical Kinetics and Combustion, Novosibirsk, Russia
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36
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Sabbir MG, Calcutt NA, Fernyhough P. Muscarinic Acetylcholine Type 1 Receptor Activity Constrains Neurite Outgrowth by Inhibiting Microtubule Polymerization and Mitochondrial Trafficking in Adult Sensory Neurons. Front Neurosci 2018; 12:402. [PMID: 29997469 PMCID: PMC6029366 DOI: 10.3389/fnins.2018.00402] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/24/2018] [Indexed: 11/13/2022] Open
Abstract
The muscarinic acetylcholine type 1 receptor (M1R) is a metabotropic G protein-coupled receptor. Knockout of M1R or exposure to selective or specific receptor antagonists elevates neurite outgrowth in adult sensory neurons and is therapeutic in diverse models of peripheral neuropathy. We tested the hypothesis that endogenous M1R activation constrained neurite outgrowth via a negative impact on the cytoskeleton and subsequent mitochondrial trafficking. We overexpressed M1R in primary cultures of adult rat sensory neurons and cell lines and studied the physiological and molecular consequences related to regulation of cytoskeletal/mitochondrial dynamics and neurite outgrowth. In adult primary neurons, overexpression of M1R caused disruption of the tubulin, but not actin, cytoskeleton and significantly reduced neurite outgrowth. Over-expression of a M1R-DREADD mutant comparatively increased neurite outgrowth suggesting that acetylcholine released from cultured neurons interacts with M1R to suppress neurite outgrowth. M1R-dependent constraint on neurite outgrowth was removed by selective (pirenzepine) or specific (muscarinic toxin 7) M1R antagonists. M1R-dependent disruption of the cytoskeleton also diminished mitochondrial abundance and trafficking in distal neurites, a disorder that was also rescued by pirenzepine or muscarinic toxin 7. M1R activation modulated cytoskeletal dynamics through activation of the G protein (Gα13) that inhibited tubulin polymerization and thus reduced neurite outgrowth. Our study provides a novel mechanism of M1R control of Gα13 protein-dependent modulation of the tubulin cytoskeleton, mitochondrial trafficking and neurite outgrowth in axons of adult sensory neurons. This novel pathway could be harnessed to treat dying-back neuropathies since anti-muscarinic drugs are currently utilized for other clinical conditions.
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Affiliation(s)
- Mohammad G Sabbir
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Centre, Winnipeg, MB, Canada
| | - Nigel A Calcutt
- Department of Pathology, University of California, San Diego, San Diego, CA, United States
| | - Paul Fernyhough
- Division of Neurodegenerative Disorders, St. Boniface Hospital Research Centre, Winnipeg, MB, Canada.,Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
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37
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Manandhar A, Kang M, Chakraborty K, Loverde SM. Effect of Nucleotide State on the Protofilament Conformation of Tubulin Octamers. J Phys Chem B 2018; 122:6164-6178. [PMID: 29768004 DOI: 10.1021/acs.jpcb.8b02193] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
At the molecular level, the dynamic instability (random growth and shrinkage) of the microtubule (MT) is driven by the nucleotide state (GTP vs GDP) in the β subunit of the tubulin dimers at the MT cap. Here, we use large-scale molecular dynamics (MD) simulations and normal-mode analysis (NMA) to characterize the effect of a single GTP cap layer on tubulin octamers composed of two neighboring protofilaments (PFs). We utilize recently reported high-resolution structures of dynamic MTs to simulate a GDP octamer both with and without a single GTP cap layer. We perform multiple replicas of long-time atomistic MD simulations (3 replicas, 0.3 μs for each replica, 0.9 μs for each octamer system, and 1.8 μs total) of both octamers. We observe that a single GTP cap layer induces structural differences in neighboring PFs, finding that one PF possesses a gradual curvature, compared to the second PF which possesses a kinked conformation. This results in either curling or splaying between these PFs. We suggest that this is due to asymmetric strengths of longitudinal contacts between the two PFs. Furthermore, using NMA, we calculate mechanical properties of these octamer systems and find that octamer system with a single GTP cap layer possesses a lower flexural rigidity.
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Affiliation(s)
- Anjela Manandhar
- Department of Chemistry, College of Staten Island , City University of New York , 2800 Victory Boulevard , Staten Island , New York 10314 , United States.,Ph.D. Program in Biochemistry , The Graduate Center of the City University of New York , 365 Fifth Avenue , New York , New York 10016 , United States
| | - Myungshim Kang
- Department of Chemistry, College of Staten Island , City University of New York , 2800 Victory Boulevard , Staten Island , New York 10314 , United States
| | - Kaushik Chakraborty
- Department of Chemistry, College of Staten Island , City University of New York , 2800 Victory Boulevard , Staten Island , New York 10314 , United States
| | - Sharon M Loverde
- Department of Chemistry, College of Staten Island , City University of New York , 2800 Victory Boulevard , Staten Island , New York 10314 , United States.,Ph.D. Program in Biochemistry , The Graduate Center of the City University of New York , 365 Fifth Avenue , New York , New York 10016 , United States
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38
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Barthélémy F, Defour A, Lévy N, Krahn M, Bartoli M. Muscle Cells Fix Breaches by Orchestrating a Membrane Repair Ballet. J Neuromuscul Dis 2018; 5:21-28. [PMID: 29480214 PMCID: PMC5836414 DOI: 10.3233/jnd-170251] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Skeletal muscle undergoes many micro-membrane lesions at physiological state. Based on their sizes and magnitude these lesions are repaired via different complexes on a specific spatio-temporal manner. One of the major repair complex is a dysferlin-dependent mechanism. Accordingly, mutations in the DYSF gene encoding dysferlin results in the development of several muscle pathologies called dysferlinopathies, where abnormalities of the membrane repair process have been characterized in patients and animal models. Recent efforts have been deployed to decipher the function of dysferlin, they shed light on its direct implication in sarcolemma resealing after injuries. These discoveries served as a strong ground to design therapeutic approaches for dysferlin-deficient patients. This review detailed the different partners and function of dysferlin and positions the sarcolemma repair in normal and pathological conditions.
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Affiliation(s)
- Florian Barthélémy
- Microbiology Immunology and Molecular Genetics, University of California, Los Angeles, CA, USA.,Center for Duchenne Muscular Dystrophy, University of California, Los Angeles, CA, USA
| | - Aurélia Defour
- Aix Marseille University, MMG, INSERM, Marseille, France
| | - Nicolas Lévy
- Aix Marseille University, MMG, INSERM, Marseille, France
| | - Martin Krahn
- Aix Marseille University, MMG, INSERM, Marseille, France
| | - Marc Bartoli
- Aix Marseille University, MMG, INSERM, Marseille, France
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39
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Bachand GD, Jain R, Ko R, Bouxsein NF, VanDelinder V. Inhibition of Microtubule Depolymerization by Osmolytes. Biomacromolecules 2018; 19:2401-2408. [PMID: 29689154 DOI: 10.1021/acs.biomac.7b01799] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Microtubule dynamics play a critical role in the normal physiology of eukaryotic cells as well as a number of cancers and neurodegenerative disorders. The polymerization/depolymerization of microtubules is regulated by a variety of stabilizing and destabilizing factors, including microtubule-associated proteins and therapeutic agents (e.g., paclitaxel, nocodazole). Here we describe the ability of the osmolytes polyethylene glycol (PEG) and trimethylamine- N-oxide (TMAO) to inhibit the depolymerization of individual microtubule filaments for extended periods of time (up to 30 days). We further show that PEG stabilizes microtubules against both temperature- and calcium-induced depolymerization. Our results collectively suggest that the observed inhibition may be related to combination of the kosmotropic behavior and excluded volume/osmotic pressure effects associated with PEG and TMAO. Taken together with prior studies, our data suggest that the physiochemical properties of the local environment can regulate microtubule depolymerization and may potentially play an important role in in vivo microtubule dynamics.
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Affiliation(s)
- George D Bachand
- Center for Integrated Nanotechnologies , Sandia National Laboratories , P.O. Box 5800, MS 1303, Albuquerque , New Mexico 87185 , United States
| | - Rishi Jain
- Center for Integrated Nanotechnologies , Sandia National Laboratories , P.O. Box 5800, MS 1303, Albuquerque , New Mexico 87185 , United States
| | - Randy Ko
- Center for Integrated Nanotechnologies , Sandia National Laboratories , P.O. Box 5800, MS 1303, Albuquerque , New Mexico 87185 , United States
| | - Nathan F Bouxsein
- Center for Integrated Nanotechnologies , Sandia National Laboratories , P.O. Box 5800, MS 1303, Albuquerque , New Mexico 87185 , United States
| | - Virginia VanDelinder
- Center for Integrated Nanotechnologies , Sandia National Laboratories , P.O. Box 5800, MS 1303, Albuquerque , New Mexico 87185 , United States
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40
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Slow Release of HIV-1 Protein Nef from Vesicle-like Structures Is Inhibited by Cytosolic Calcium Elevation in Single Human Microglia. Mol Neurobiol 2018; 56:102-118. [DOI: 10.1007/s12035-018-1072-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 04/09/2018] [Indexed: 12/14/2022]
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41
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Fees CP, Moore JK. Regulation of microtubule dynamic instability by the carboxy-terminal tail of β-tubulin. Life Sci Alliance 2018; 1. [PMID: 29963657 PMCID: PMC6022761 DOI: 10.26508/lsa.201800054] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
This work examines how the carboxy-terminal tail domain of β-tubulin governs microtubule dynamic instability and the structure of plus ends using complementary in vivo and in vitro experiments. Dynamic instability is an intrinsic property of microtubules; however, we do not understand what domains of αβ-tubulins regulate this activity or how these regulate microtubule networks in cells. Here, we define a role for the negatively charged carboxy-terminal tail (CTT) domain of β-tubulin in regulating dynamic instability. By combining in vitro studies with purified mammalian tubulin and in vivo studies with tubulin mutants in budding yeast, we demonstrate that β-tubulin CTT inhibits microtubule stability and regulates the structure and stability of microtubule plus ends. Tubulin that lacks β-tubulin CTT polymerizes faster and depolymerizes slower in vitro and forms microtubules that are more prone to catastrophe. The ends of these microtubules exhibit a more blunted morphology and rapidly switch to disassembly after tubulin depletion. In addition, we show that β-tubulin CTT is required for magnesium cations to promote depolymerization. We propose that β-tubulin CTT regulates the assembly of stable microtubule ends and provides a tunable mechanism to coordinate dynamic instability with ionic strength in the cell.
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Affiliation(s)
- Colby P Fees
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO, USA
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42
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Duhamel M, Rose M, Rodet F, Murgoci AN, Zografidou L, Régnier-Vigouroux A, Vanden Abeele F, Kobeissy F, Nataf S, Pays L, Wisztorski M, Cizkova D, Fournier I, Salzet M. Paclitaxel Treatment and Proprotein Convertase 1/3 (PC1/3) Knockdown in Macrophages is a Promising Antiglioma Strategy as Revealed by Proteomics and Cytotoxicity Studies. Mol Cell Proteomics 2018. [PMID: 29531019 DOI: 10.1074/mcp.ra117.000443] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
High grade gliomas are the most common brain tumors in adult. These tumors are characterized by a high infiltration in microglial cells and macrophages. The immunosuppressive tumor environment is known to orient immune cells toward a pro-tumoral and anti-inflammatory phenotype. Therefore, the current challenge for cancer therapy is to find a way to reorient macrophages toward an antitumoral phenotype. Previously, we demonstrated that macrophages secreted antitumoral factors when they were invalidated for the proprotein converstase 1/3 (PC1/3) and treated with LPS. However, achieving an activation of macrophages via LPS/TLR4/Myd88-dependent pathway appears yet unfeasible in cancer patients. On the contrary, the antitumor drug Paclitaxel is also known to activate the TLR4 MyD88-dependent signaling pathway and mimics LPS action. Therefore, we evaluated if PC1/3 knock-down (KD) macrophages could be activated by Paclitaxel and efficient against glioma. We report here that such a treatment of PC1/3 KD macrophages drove to the overexpression of proteins mainly involved in cytoskeleton rearrangement. In support of this finding, we found that these cells exhibited a Ca2+ increase after Paclitaxel treatment. This is indicative of a possible depolymerization of microtubules and may therefore reflect an activation of inflammatory pathways in macrophages. In such a way, we found that PC1/3 KD macrophages displayed a repression of the anti-inflammatory pathway STAT3 and secreted more pro-inflammatory cytokines. Extracellular vesicles isolated from these PC1/3 KD cells inhibited glioma growth. Finally, the supernatant collected from the coculture between glioma cells and PC1/3 KD macrophages contained more antitumoral factors. These findings unravel the potential value of a new therapeutic strategy combining Paclitaxel and PC1/3 inhibition to switch macrophages toward an antitumoral immunophenotype.
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Affiliation(s)
- Marie Duhamel
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France;
| | - Mélanie Rose
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France.,§Oncovet Clinical Research (OCR), SIRIC ONCOLille, Villeneuve d'Ascq, France
| | - Franck Rodet
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France
| | - Adriana Natalia Murgoci
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France.,§§Institute of Neuroimmunology, Slovak Academy of Sciences, 845 10, Bratislava, Slovak Republic
| | - Lea Zografidou
- ¶Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 15, D-55128 Mainz, Germany
| | - Anne Régnier-Vigouroux
- ¶Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 15, D-55128 Mainz, Germany
| | - Fabien Vanden Abeele
- ‖Inserm U-1003, Equipe labellisée par la Ligue Nationale contre le cancer, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université Lille 1, Cité Scientifique, 59655 Villeneuve d'Ascq, France
| | - Firas Kobeissy
- **Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, 1107 2020 Beirut, Lebanon
| | - Serge Nataf
- ‡‡Inserm U-1060, CarMeN Laboratory, Banque de Tissus et de Cellules des Hospices Civils de Lyon, Université Lyon-1, Hôpital Edouard Herriot, 69437 Lyon cedex 03, France
| | - Laurent Pays
- ‡‡Inserm U-1060, CarMeN Laboratory, Banque de Tissus et de Cellules des Hospices Civils de Lyon, Université Lyon-1, Hôpital Edouard Herriot, 69437 Lyon cedex 03, France
| | - Maxence Wisztorski
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France
| | - Dasa Cizkova
- §§Institute of Neuroimmunology, Slovak Academy of Sciences, 845 10, Bratislava, Slovak Republic
| | - Isabelle Fournier
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France
| | - Michel Salzet
- From the ‡Inserm U-1192, Laboratoire de Protéomique, Réponse Inflammatoire, Spectrométrie de Masse (PRISM), Université Lille 1, Cité Scientifique, 59655 Villeneuve D'Ascq, France
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43
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Abstract
We present a simple physically based quantitative model of blood platelet shape and its evolution during agonist-induced activation. The model is based on the consideration of two major cytoskeletal elements: the marginal band of microtubules and the submembrane cortex. Mathematically, we consider the problem of minimization of surface area constrained to confine the marginal band and a certain cellular volume. For resting platelets, the marginal band appears as a peripheral ring, allowing for the analytical solution of the minimization problem. Upon activation, the marginal band coils out of plane and forms 3D convoluted structure. We show that its shape is well approximated by an overcurved circle, a mathematical concept of closed curve with constant excessive curvature. Possible mechanisms leading to such marginal band coiling are discussed, resulting in simple parametric expression for the marginal band shape during platelet activation. The excessive curvature of marginal band is a convenient state variable which tracks the progress of activation. The cell surface is determined using numerical optimization. The shapes are strictly mathematically defined by only three parameters and show good agreement with literature data. They can be utilized in simulation of platelets interaction with different physical fields, e.g. for the description of hydrodynamic and mechanical properties of platelets, leading to better understanding of platelets margination and adhesion and thrombus formation in blood flow. It would also facilitate precise characterization of platelets in clinical diagnosis, where a novel optical model is needed for the correct solution of inverse light-scattering problem.
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44
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Pan S, Chan JR. Regulation and dysregulation of axon infrastructure by myelinating glia. J Cell Biol 2017; 216:3903-3916. [PMID: 29114067 PMCID: PMC5716274 DOI: 10.1083/jcb.201702150] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/06/2017] [Accepted: 10/18/2017] [Indexed: 12/21/2022] Open
Abstract
Pan and Chan discuss the role of myelinating glia in axonal development and the impact of demyelination on axon degeneration. Axon loss and neurodegeneration constitute clinically debilitating sequelae in demyelinating diseases such as multiple sclerosis, but the underlying mechanisms of secondary degeneration are not well understood. Myelinating glia play a fundamental role in promoting the maturation of the axon cytoskeleton, regulating axon trafficking parameters, and imposing architectural rearrangements such as the nodes of Ranvier and their associated molecular domains. In the setting of demyelination, these changes may be reversed or persist as maladaptive features, leading to axon degeneration. In this review, we consider recent insights into axon–glial interactions during development and disease to propose that disruption of the cytoskeleton, nodal architecture, and other components of axon infrastructure is a potential mediator of pathophysiological damage after demyelination.
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Affiliation(s)
- Simon Pan
- Department of Neurology, University of California, San Francisco, San Francisco, CA .,Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA
| | - Jonah R Chan
- Department of Neurology, University of California, San Francisco, San Francisco, CA.,Neuroscience Graduate Program, University of California, San Francisco, San Francisco, CA
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45
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Liu Y, Visetsouk M, Mynlieff M, Qin H, Lechtreck KF, Yang P. H +- and Na +- elicited rapid changes of the microtubule cytoskeleton in the biflagellated green alga Chlamydomonas. eLife 2017; 6:26002. [PMID: 28875932 PMCID: PMC5779235 DOI: 10.7554/elife.26002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 09/05/2017] [Indexed: 12/27/2022] Open
Abstract
Although microtubules are known for dynamic instability, the dynamicity is considered to be tightly controlled to support a variety of cellular processes. Yet diverse evidence suggests that this is not applicable to Chlamydomonas, a biflagellate fresh water green alga, but intense autofluorescence from photosynthesis pigments has hindered the investigation. By expressing a bright fluorescent reporter protein at the endogenous level, we demonstrate in real time discreet sweeping changes in algal microtubules elicited by rises of intracellular H+ and Na+. These results from this model organism with characteristics of animal and plant cells provide novel explanations regarding how pH may drive cellular processes; how plants may respond to, and perhaps sense stresses; and how organisms with a similar sensitive cytoskeleton may be susceptible to environmental changes.
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Affiliation(s)
- Yi Liu
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Mike Visetsouk
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Michelle Mynlieff
- Department of Biological Sciences, Marquette University, Milwaukee, United States
| | - Hongmin Qin
- Department of Biology, Texas A&M University, College Station, United States
| | - Karl F Lechtreck
- Department of Cellular Biology, University of Georgia, Athen, United States
| | - Pinfen Yang
- Department of Biological Sciences, Marquette University, Milwaukee, United States
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46
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Hill CE. A view from the ending: Axonal dieback and regeneration following SCI. Neurosci Lett 2017; 652:11-24. [DOI: 10.1016/j.neulet.2016.11.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/20/2016] [Accepted: 11/01/2016] [Indexed: 12/22/2022]
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47
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Carr L, Bardet SM, Burke RC, Arnaud-Cormos D, Leveque P, O'Connor RP. Calcium-independent disruption of microtubule dynamics by nanosecond pulsed electric fields in U87 human glioblastoma cells. Sci Rep 2017; 7:41267. [PMID: 28117459 PMCID: PMC5259788 DOI: 10.1038/srep41267] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 12/19/2016] [Indexed: 12/26/2022] Open
Abstract
High powered, nanosecond duration, pulsed electric fields (nsPEF) cause cell death by a mechanism that is not fully understood and have been proposed as a targeted cancer therapy. Numerous chemotherapeutics work by disrupting microtubules. As microtubules are affected by electrical fields, this study looks at the possibility of disrupting them electrically with nsPEF. Human glioblastoma cells (U87-MG) treated with 100, 10 ns, 44 kV/cm pulses at a frequency of 10 Hz showed a breakdown of their interphase microtubule network that was accompanied by a reduction in the number of growing microtubules. This effect is temporally linked to loss of mitochondrial membrane potential and independent of cellular swelling and calcium influx, two factors that disrupt microtubule growth dynamics. Super-resolution microscopy revealed microtubule buckling and breaking as a result of nsPEF application, suggesting that nsPEF may act directly on microtubules.
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Affiliation(s)
- Lynn Carr
- XLIM Research Institute, UMR CNRS No 7252, University of Limoges, Faculty of Science and Techniques, 123 Avenue Albert Thomas, 87060 Limoges, France
| | - Sylvia M Bardet
- XLIM Research Institute, UMR CNRS No 7252, University of Limoges, Faculty of Science and Techniques, 123 Avenue Albert Thomas, 87060 Limoges, France
| | - Ryan C Burke
- XLIM Research Institute, UMR CNRS No 7252, University of Limoges, Faculty of Science and Techniques, 123 Avenue Albert Thomas, 87060 Limoges, France
| | - Delia Arnaud-Cormos
- XLIM Research Institute, UMR CNRS No 7252, University of Limoges, Faculty of Science and Techniques, 123 Avenue Albert Thomas, 87060 Limoges, France
| | - Philippe Leveque
- XLIM Research Institute, UMR CNRS No 7252, University of Limoges, Faculty of Science and Techniques, 123 Avenue Albert Thomas, 87060 Limoges, France
| | - Rodney P O'Connor
- XLIM Research Institute, UMR CNRS No 7252, University of Limoges, Faculty of Science and Techniques, 123 Avenue Albert Thomas, 87060 Limoges, France
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48
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Betsch L, Savarin J, Bendahmane M, Szecsi J. Roles of the Translationally Controlled Tumor Protein (TCTP) in Plant Development. Results Probl Cell Differ 2017; 64:149-172. [PMID: 29149407 DOI: 10.1007/978-3-319-67591-6_7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The Translationally Controlled Tumor Protein (TCTP) is a conserved protein which expression was associated with several biochemical and cellular functions. Loss-of-function mutants are lethal both in animals and in plants, making the identification of its exact role difficult. Recent data using the model plant Arabidopsis thaliana provided the first viable adult knockout for TCTP and helped addressing the biological role of TCTP during organ development and the functional conservation between plants and animals. This chapter summarizes our up to date knowledge about the role of TCTP in plants and discuss about conserved functions and mechanisms between plants and animals.
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Affiliation(s)
- Léo Betsch
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS, INRA, 69342, Lyon, France
| | - Julie Savarin
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS, INRA, 69342, Lyon, France
| | - Mohammed Bendahmane
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS, INRA, 69342, Lyon, France.
| | - Judit Szecsi
- Laboratoire Reproduction et Développement des Plantes, Univ Lyon, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS, INRA, 69342, Lyon, France.
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49
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Clark JA, Yeaman EJ, Blizzard CA, Chuckowree JA, Dickson TC. A Case for Microtubule Vulnerability in Amyotrophic Lateral Sclerosis: Altered Dynamics During Disease. Front Cell Neurosci 2016; 10:204. [PMID: 27679561 PMCID: PMC5020100 DOI: 10.3389/fncel.2016.00204] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/15/2016] [Indexed: 12/11/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is an aggressive multifactorial disease converging on a common pathology: the degeneration of motor neurons (MNs), their axons and neuromuscular synapses. This vulnerability and dysfunction of MNs highlights the dependency of these large cells on their intracellular machinery. Neuronal microtubules (MTs) are intracellular structures that facilitate a myriad of vital neuronal functions, including activity dependent axonal transport. In ALS, it is becoming increasingly apparent that MTs are likely to be a critical component of this disease. Not only are disruptions in this intracellular machinery present in the vast majority of seemingly sporadic cases, recent research has revealed that mutation to a microtubule protein, the tubulin isoform TUBA4A, is sufficient to cause a familial, albeit rare, form of disease. In both sporadic and familial disease, studies have provided evidence that microtubule mediated deficits in axonal transport are the tipping point for MN survivability. Axonal transport deficits would lead to abnormal mitochondrial recycling, decreased vesicle and mRNA transport and limited signaling of key survival factors from the neurons peripheral synapses, causing the characteristic peripheral "die back". This disruption to microtubule dependant transport in ALS has been shown to result from alterations in the phenomenon of microtubule dynamic instability: the rapid growth and shrinkage of microtubule polymers. This is accomplished primarily due to aberrant alterations to microtubule associated proteins (MAPs) that regulate microtubule stability. Indeed, the current literature would argue that microtubule stability, particularly alterations in their dynamics, may be the initial driving force behind many familial and sporadic insults in ALS. Pharmacological stabilization of the microtubule network offers an attractive therapeutic strategy in ALS; indeed it has shown promise in many neurological disorders, ALS included. However, the pathophysiological involvement of MTs and their functions is still poorly understood in ALS. Future investigations will hopefully uncover further therapeutic targets that may aid in combating this awful disease.
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Affiliation(s)
- Jayden A Clark
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Elise J Yeaman
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Catherine A Blizzard
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Jyoti A Chuckowree
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
| | - Tracey C Dickson
- Menzies Institute for Medical Research, University of Tasmania Hobart, TAS, Australia
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50
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Bodaleo FJ, Gonzalez-Billault C. The Presynaptic Microtubule Cytoskeleton in Physiological and Pathological Conditions: Lessons from Drosophila Fragile X Syndrome and Hereditary Spastic Paraplegias. Front Mol Neurosci 2016; 9:60. [PMID: 27504085 PMCID: PMC4958632 DOI: 10.3389/fnmol.2016.00060] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 07/11/2016] [Indexed: 11/21/2022] Open
Abstract
The capacity of the nervous system to generate neuronal networks relies on the establishment and maintenance of synaptic contacts. Synapses are composed of functionally different presynaptic and postsynaptic compartments. An appropriate synaptic architecture is required to provide the structural basis that supports synaptic transmission, a process involving changes in cytoskeletal dynamics. Actin microfilaments are the main cytoskeletal components present at both presynaptic and postsynaptic terminals in glutamatergic synapses. However, in the last few years it has been demonstrated that microtubules (MTs) transiently invade dendritic spines, promoting their maturation. Nevertheless, the presence and functions of MTs at the presynaptic site are still a matter of debate. Early electron microscopy (EM) studies revealed that MTs are present in the presynaptic terminals of the central nervous system (CNS) where they interact with synaptic vesicles (SVs) and reach the active zone. These observations have been reproduced by several EM protocols; however, there is empirical heterogeneity in detecting presynaptic MTs, since they appear to be both labile and unstable. Moreover, increasing evidence derived from studies in the fruit fly neuromuscular junction proposes different roles for MTs in regulating presynaptic function in physiological and pathological conditions. In this review, we summarize the main findings that support the presence and roles of MTs at presynaptic terminals, integrating descriptive and biochemical analyses, and studies performed in invertebrate genetic models.
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Affiliation(s)
- Felipe J Bodaleo
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO)Santiago, Chile
| | - Christian Gonzalez-Billault
- Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile; Center for Geroscience, Brain Health and Metabolism (GERO)Santiago, Chile; The Buck Institute for Research on Aging, NovatoCA, USA
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