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Carabajal MPA, Bonacina J, Scarinci N, Albarracín VH, Cantero MDR, Cantiello HF. The bacterial tubulin homolog FtsZ generates electrical oscillations. Biochem Biophys Res Commun 2023; 687:149186. [PMID: 37931420 DOI: 10.1016/j.bbrc.2023.149186] [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: 08/13/2023] [Revised: 10/23/2023] [Accepted: 10/30/2023] [Indexed: 11/08/2023]
Abstract
FtsZ, a major cytoskeletal protein in all bacteria and archaea, forms a ring that directs cytokinesis. Bacterial FtsZ is considered the ancestral homolog of the eukaryotic microtubule (MT)-forming tubulins, sharing GTPase activity and the ability to assemble into protofilaments, rings, and sheets, but not MTs. Previous studies from our laboratory demonstrated that structures of isolated brain MTs spontaneously generate electrical oscillations and bursts of electrical activity similar to action potentials. No information about whether the prokaryotic tubulins may share similar properties is available. Here, we obtained by ammonium sulfate precipitation an enriched protein fraction of the endogenous FtsZ from wild-type Escherichia coli ATCC 25922 without any transfection or overexpression of the protein. As revealed by electron microscopy, FtsZ was detected by dot blot analysis and immunofluorescence that assembled into filaments and sheets in a polymerization buffer. We used the patch-clamp technique to explore the electrical properties of sheets of FtsZ and bacterial cells. Electrical recordings at various holding potentials ranging from ±200 mV showed a complex oscillatory behavior, with several peak frequencies between 12 and 110 Hz in the power spectra and a linear mean current response. To confirm the oscillatory electrical behavior of FtsZ we also conducted experiments with commercial recombinant FtsZ, with similar results. We also detected, by local field potentials, similar electrical oscillations in K+-depolarized pellets of E. coli cultures. FtsZ oscillations had a wider range of frequency peaks than MT sheets from eukaryotic origin. The findings indicate that the bacterial cytoskeleton generates electrical oscillators that may play a relevant role in cell division and unknown signaling mechanisms in bacterial populations.
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Affiliation(s)
- Mónica P A Carabajal
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, 4206, Argentina
| | - Julieta Bonacina
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, 4206, Argentina
| | - Noelia Scarinci
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, 4206, Argentina
| | - Virginia H Albarracín
- Centro Integral de Microscopía Electrónica (CIME, CONICET-UNT), Yerba Buena, 4107, Tucumán, Argentina
| | - María Del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, 4206, Argentina
| | - Horacio F Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, 4206, Argentina.
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2
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Gutierrez BC, Cantiello HF, Cantero MDR. The electrical properties of isolated microtubules. Sci Rep 2023; 13:10165. [PMID: 37349383 PMCID: PMC10287629 DOI: 10.1038/s41598-023-36801-1] [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: 01/17/2023] [Accepted: 06/12/2023] [Indexed: 06/24/2023] Open
Abstract
This study examines the electrical properties of isolated brain microtubules (MTs), which are long hollow cylinders assembled from αβ-tubulin dimers that form cytoskeletal structures engaged in several functions. MTs are implicated in sensory functions in cilia and flagella and cellular activities that range from cell motility, vesicular traffic, and neuronal processes to cell division in the centrosomes and centrioles. We determined the electrical properties of the MTs with the loose patch clamp technique in either the presence or absence of the MT stabilizer Paclitaxel. We observed electrical oscillations at different holding potentials that responded accordingly in amplitude and polarity. At zero mV in symmetrical ionic conditions, a single MT radiated an electrical power of 10-17 W. The spectral analysis of the time records disclosed a single fundamental peak at 39 Hz in the Paclitaxel-stabilized MTs. However, a richer oscillatory response and two mean conductances were observed in the non-Paclitaxel MTs. The findings evidence that the brain MTs are electrical oscillators that behave as "ionic-based" transistors to generate, propagate, and amplify electrical signals.
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Affiliation(s)
- Brenda C Gutierrez
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina
| | - Horacio F Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina
| | - María Del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina.
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3
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Tuszynski JA, Costa F. Low-energy amplitude-modulated radiofrequency electromagnetic fields as a systemic treatment for cancer: Review and proposed mechanisms of action. FRONTIERS IN MEDICAL TECHNOLOGY 2022; 4:869155. [PMID: 36157082 PMCID: PMC9498185 DOI: 10.3389/fmedt.2022.869155] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 08/19/2022] [Indexed: 11/13/2022] Open
Abstract
Exposure to Low-Energy Amplitude-Modulated Radiofrequency Electromagnetic Fields (LEAMRFEMF) represents a new treatment option for patients with advanced hepatocellular carcinoma (AHCC). We focus on two medical devices that modulate the amplitude of a 27.12 MHz carrier wave to generate envelope waves in the low Hz to kHz range. Each provides systemic exposure to LEAMRFEMF via an intrabuccal antenna. This technology differs from so-called Tumour Treating Fields because it uses different frequency ranges, uses electromagnetic rather than electric fields, and delivers energy systemically rather than locally. The AutemDev also deploys patient-specific frequencies. LEAMRFEMF devices use 100-fold less power than mobile phones and have no thermal effects on tissue. Tumour type-specific or patient-specific treatment frequencies can be derived by measuring haemodynamic changes induced by exposure to LEAMRFEMF. These specific frequencies inhibited growth of human cancer cell lines in vitro and in mouse xenograft models. In uncontrolled prospective clinical trials in patients with AHCC, minorities of patients experienced complete or partial tumour responses. Pooled comparisons showed enhanced overall survival in treated patients compared to historical controls. Mild transient somnolence was the only notable treatment-related adverse event. We hypothesize that intracellular oscillations of charged macromolecules and ion flows couple resonantly with LEAMRFEMF. This resonant coupling appears to disrupt cell division and subcellular trafficking of mitochondria. We provide an estimate of the contribution of the electromagnetic effects to the overall energy balance of an exposed cell by calculating the power delivered to the cell, and the energy dissipated through the cell due to EMF induction of ionic flows along microtubules. We then compare this with total cellular metabolic energy production and conclude that energy delivered by LEAMRFEMF may provide a beneficial shift in cancer cell metabolism away from aberrant glycolysis. Further clinical research may confirm that LEAMRFEMF has therapeutic value in AHCC.
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Affiliation(s)
- Jack A. Tuszynski
- Division of Experimental Oncology, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton, AB, Canada
- Dipartimento di Ingegneria Meccanica e Aerospaziale, Politecnico di Torino, Turin, Italy
- Autem Therapeutics, Hanover, NH, United States
- Correspondence: Jack A. Tuszynski
| | - Frederico Costa
- Autem Therapeutics, Hanover, NH, United States
- Oncology Department, Hospital Sírio-Libanês, São Paulo, Brazil
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4
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Priel A, Dai XQ, Chen XZ, Scarinci N, Cantero MDR, Cantiello HF. Electrical recordings from dendritic spines of adult mouse hippocampus and effect of the actin cytoskeleton. Front Mol Neurosci 2022; 15:769725. [PMID: 36090255 PMCID: PMC9453158 DOI: 10.3389/fnmol.2022.769725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 07/26/2022] [Indexed: 11/28/2022] Open
Abstract
Dendritic spines (DS) are tiny protrusions implicated in excitatory postsynaptic responses in the CNS. To achieve their function, DS concentrate a high density of ion channels and dynamic actin networks in a tiny specialized compartment. However, to date there is no direct information on DS ionic conductances. Here, we used several experimental techniques to obtain direct electrical information from DS of the adult mouse hippocampus. First, we optimized a method to isolate DS from the dissected hippocampus. Second, we used the lipid bilayer membrane (BLM) reconstitution and patch clamping techniques and obtained heretofore unavailable electrical phenotypes on ion channels present in the DS membrane. Third, we also patch clamped DS directly in cultured adult mouse hippocampal neurons, to validate the electrical information observed with the isolated preparation. Electron microscopy and immunochemistry of PDS-95 and NMDA receptors and intrinsic actin networks confirmed the enrichment of the isolated DS preparation, showing open and closed DS, and multi-headed DS. The preparation was used to identify single channel activities and “whole-DS” electrical conductance. We identified NMDA and Ca2+-dependent intrinsic electrical activity in isolated DS and in situ DS of cultured adult mouse hippocampal neurons. In situ recordings in the presence of local NMDA, showed that individual DS intrinsic electrical activity often back-propagated to the dendrite from which it sprouted. The DS electrical oscillations were modulated by changes in actin cytoskeleton dynamics by addition of the F-actin disrupter agent, cytochalasin D, and exogenous actin-binding proteins. The data indicate that DS are elaborate excitable electrical devices, whose activity is a functional interplay between ion channels and the underlying actin networks. The data argue in favor of the active contribution of individual DS to the electrical activity of neurons at the level of both the membrane conductance and cytoskeletal signaling.
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Affiliation(s)
- Avner Priel
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Xiao-Qing Dai
- Department of Pharmacology, Alberta Diabetes Institute, University of Alberta, Edmonton, AB, Canada
| | - Xing-Zhen Chen
- Department of Physiology, University of Alberta, Edmonton, AB, Canada
| | - Noelia Scarinci
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina (CONICET) - Universidad Nacional de Santiago del Estero (UNSE), Santiago del Estero, Argentina
| | - María del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina (CONICET) - Universidad Nacional de Santiago del Estero (UNSE), Santiago del Estero, Argentina
| | - Horacio F. Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo, Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina (CONICET) - Universidad Nacional de Santiago del Estero (UNSE), Santiago del Estero, Argentina
- *Correspondence: Horacio F. Cantiello,
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Hameroff S. Consciousness, Cognition and the Neuronal Cytoskeleton - A New Paradigm Needed in Neuroscience. Front Mol Neurosci 2022; 15:869935. [PMID: 35782391 PMCID: PMC9245524 DOI: 10.3389/fnmol.2022.869935] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Accepted: 04/20/2022] [Indexed: 12/03/2022] Open
Abstract
Viewing the brain as a complex computer of simple neurons cannot account for consciousness nor essential features of cognition. Single cell organisms with no synapses perform purposeful intelligent functions using their cytoskeletal microtubules. A new paradigm is needed to view the brain as a scale-invariant hierarchy extending both upward from the level of neurons to larger and larger neuronal networks, but also downward, inward, to deeper, faster quantum and classical processes in cytoskeletal microtubules inside neurons. Evidence shows self-similar patterns of conductive resonances repeating in terahertz, gigahertz, megahertz, kilohertz and hertz frequency ranges in microtubules. These conductive resonances apparently originate in terahertz quantum dipole oscillations and optical interactions among pi electron resonance clouds of aromatic amino acid rings of tryptophan, phenylalanine and tyrosine within each tubulin, the component subunit of microtubules, and the brain's most abundant protein. Evidence from cultured neuronal networks also now shows that gigahertz and megahertz oscillations in dendritic-somatic microtubules regulate specific firings of distal axonal branches, causally modulating membrane and synaptic activities. The brain should be viewed as a scale-invariant hierarchy, with quantum and classical processes critical to consciousness and cognition originating in microtubules inside neurons.
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Affiliation(s)
- Stuart Hameroff
- Department of Anesthesiology, The University of Arizona, Tucson, AZ, United States
- Department of Psychology, The University of Arizona, Tucson, AZ, United States
- Center for Consciousness Studies, The University of Arizona, Tucson, AZ, United States
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6
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Tassinari R, Cavallini C, Olivi E, Facchin F, Taglioli V, Zannini C, Marcuzzi M, Ventura C. Cell Responsiveness to Physical Energies: Paving the Way to Decipher a Morphogenetic Code. Int J Mol Sci 2022; 23:ijms23063157. [PMID: 35328576 PMCID: PMC8949133 DOI: 10.3390/ijms23063157] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 02/04/2023] Open
Abstract
We discuss emerging views on the complexity of signals controlling the onset of biological shapes and functions, from the nanoarchitectonics arising from supramolecular interactions, to the cellular/multicellular tissue level, and up to the unfolding of complex anatomy. We highlight the fundamental role of physical forces in cellular decisions, stressing the intriguing similarities in early morphogenesis, tissue regeneration, and oncogenic drift. Compelling evidence is presented, showing that biological patterns are strongly embedded in the vibrational nature of the physical energies that permeate the entire universe. We describe biological dynamics as informational processes at which physics and chemistry converge, with nanomechanical motions, and electromagnetic waves, including light, forming an ensemble of vibrations, acting as a sort of control software for molecular patterning. Biomolecular recognition is approached within the establishment of coherent synchronizations among signaling players, whose physical nature can be equated to oscillators tending to the coherent synchronization of their vibrational modes. Cytoskeletal elements are now emerging as senders and receivers of physical signals, "shaping" biological identity from the cellular to the tissue/organ levels. We finally discuss the perspective of exploiting the diffusive features of physical energies to afford in situ stem/somatic cell reprogramming, and tissue regeneration, without stem cell transplantation.
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Affiliation(s)
- Riccardo Tassinari
- ELDOR LAB, National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Via Gobetti 101, 40129 Bologna, Italy; (R.T.); (C.C.); (E.O.); (V.T.); (C.Z.)
| | - Claudia Cavallini
- ELDOR LAB, National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Via Gobetti 101, 40129 Bologna, Italy; (R.T.); (C.C.); (E.O.); (V.T.); (C.Z.)
| | - Elena Olivi
- ELDOR LAB, National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Via Gobetti 101, 40129 Bologna, Italy; (R.T.); (C.C.); (E.O.); (V.T.); (C.Z.)
| | - Federica Facchin
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Via Massarenti 9, 40138 Bologna, Italy;
| | - Valentina Taglioli
- ELDOR LAB, National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Via Gobetti 101, 40129 Bologna, Italy; (R.T.); (C.C.); (E.O.); (V.T.); (C.Z.)
| | - Chiara Zannini
- ELDOR LAB, National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Via Gobetti 101, 40129 Bologna, Italy; (R.T.); (C.C.); (E.O.); (V.T.); (C.Z.)
| | - Martina Marcuzzi
- INBB, Biostructures and Biosystems National Institute, Viale Medaglie d’Oro 305, 00136 Rome, Italy;
| | - Carlo Ventura
- ELDOR LAB, National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Via Gobetti 101, 40129 Bologna, Italy; (R.T.); (C.C.); (E.O.); (V.T.); (C.Z.)
- Correspondence: ; Tel.: +39-347-920-6992
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7
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Gutierrez BC, Pita Almenar MR, Martínez LJ, Siñeriz Louis M, Albarracín VH, Cantero MDR, Cantiello HF. Honeybee Brain Oscillations Are Generated by Microtubules. The Concept of a Brain Central Oscillator. Front Mol Neurosci 2021; 14:727025. [PMID: 34658784 PMCID: PMC8511451 DOI: 10.3389/fnmol.2021.727025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 09/06/2021] [Indexed: 12/30/2022] Open
Abstract
Microtubules (MTs) are important structures of the cytoskeleton in neurons. Mammalian brain MTs act as biomolecular transistors that generate highly synchronous electrical oscillations. However, their role in brain function is largely unknown. To gain insight into the MT electrical oscillatory activity of the brain, we turned to the honeybee (Apis mellifera) as a useful model to isolate brains and MTs. The patch clamp technique was applied to MT sheets of purified honeybee brain MTs. High resistance seal patches showed electrical oscillations that linearly depended on the holding potential between ± 200 mV and had an average conductance in the order of ~9 nS. To place these oscillations in the context of the brain, we also explored local field potential (LFP) recordings from the Triton X-permeabilized whole honeybee brain unmasking spontaneous oscillations after but not before tissue permeabilization. Frequency domain spectral analysis of time records indicated at least two major peaks at approximately ~38 Hz and ~93 Hz in both preparations. The present data provide evidence that MT electrical oscillations are a novel signaling mechanism implicated in brain wave activity observed in the insect brain.
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Affiliation(s)
- Brenda C. Gutierrez
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina
| | - Marcelo R. Pita Almenar
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina
| | - Luciano J. Martínez
- Centro Integral de Microscopía Electrónica (CIME-CONICET-UNT), Tucumán, Argentina
| | - Manuel Siñeriz Louis
- Centro Integral de Microscopía Electrónica (CIME-CONICET-UNT), Tucumán, Argentina
| | | | - María del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina
| | - Horacio F. Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, CONICET-UNSE), Santiago del Estero, Argentina
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8
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Calcium signal transmission by axonemal microtubules as an optimized information pathway in cilia and flagella. J Bioenerg Biomembr 2021; 53:633-641. [PMID: 34537954 DOI: 10.1007/s10863-021-09920-5] [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: 05/21/2021] [Accepted: 09/07/2021] [Indexed: 10/20/2022]
Abstract
Calcium plays a key role in signal transduction in eukaryotic cells. Besides controlling local functions of cells calcium ions are responsible for the generation of global signals such as waves and spikes. Pulsatile increases of calcium concentrations are generally considered to have a much higher fidelity of information transfer than simple tonic changes, since they are much less prone to noisy fluctuations. In that respect, it was clearly revealed that Ca2+ has very crucial involvement in many signaling pathways in cilia and flagella. We earlier established a model in which axonemal microtubules exhibit the features of nonlinear polyelectrolitic electric transmissions lines for efficient transport of cations, primarily Ca2+. These microtubules guide accumulated "ionic clods" which serve as the pulsatile signals aimed to regulate pertaining motor proteins, dyneins and kinesis. We here consider such Ca2+ signals in axoneme in the context of Shannon's and Fisher's information theories. It appears that the fast drift of these "ionic clouds" represents the optimized calcium signaling for control of "flagellary beats" as well as intraflagellary transport of proteins essential for the construction, elongation and maintenance of eukaryotic cilia and flagella themselves.
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9
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Vissol-Gaudin E, Pearson C, Groves C, Zeze DA, Cantiello HF, Cantero MDR, Petty MC. Electrical behaviour and evolutionary computation in thin films of bovine brain microtubules. Sci Rep 2021; 11:10776. [PMID: 34031499 PMCID: PMC8144580 DOI: 10.1038/s41598-021-90260-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 04/12/2021] [Indexed: 11/10/2022] Open
Abstract
We report on the electrical behaviour of thin films of bovine brain microtubules (MTs). For samples in both their dried and hydrated states, the measured currents reveal a power law dependence on the applied DC voltage. We attribute this to the injection of space-charge from the metallic electrode(s). The MTs are thought to form a complex electrical network, which can be manipulated with an applied voltage. This feature has been exploited to undertake some experiments on the use of the MT mesh as a medium for computation. We show that it is possible to evolve MT films into binary classifiers following an evolution in materio approach. The accuracy of the system is, on average, similar to that of early carbon nanotube classifiers developed using the same methodology.
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Affiliation(s)
| | - Chris Pearson
- Department of Engineering, Durham University, South Road, Durham, DH1 3LE, UK
| | - Chris Groves
- Department of Engineering, Durham University, South Road, Durham, DH1 3LE, UK
| | - Dagou A Zeze
- Department of Engineering, Durham University, South Road, Durham, DH1 3LE, UK
| | - Horacio F Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología Y Desarrollo (IMSaTeD, CONICET-UNSE), Villa El Zanjón, 4206, Santiago del Estero, Argentina
| | - María Del Rocio Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología Y Desarrollo (IMSaTeD, CONICET-UNSE), Villa El Zanjón, 4206, Santiago del Estero, Argentina
| | - Michael C Petty
- Department of Engineering, Durham University, South Road, Durham, DH1 3LE, UK.
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10
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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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11
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Affiliation(s)
- Susan K Kozawa
- Department of Macromolecular Science and Engineering Case Western Reserve University Cleveland OH USA
| | - Gary E Wnek
- Department of Macromolecular Science and Engineering Case Western Reserve University Cleveland OH USA
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12
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Satarić MV, Nemeš T, Satarić B, Sekulić D, Zdravković S. Calcium ions tune the beats of cilia and flagella. Biosystems 2020; 196:104172. [DOI: 10.1016/j.biosystems.2020.104172] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 05/13/2020] [Accepted: 05/13/2020] [Indexed: 01/19/2023]
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13
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Saternos H, Ley S, AbouAlaiwi W. Primary Cilia and Calcium Signaling Interactions. Int J Mol Sci 2020; 21:E7109. [PMID: 32993148 PMCID: PMC7583801 DOI: 10.3390/ijms21197109] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/23/2020] [Accepted: 09/24/2020] [Indexed: 02/06/2023] Open
Abstract
The calcium ion (Ca2+) is a diverse secondary messenger with a near-ubiquitous role in a vast array of cellular processes. Cilia are present on nearly every cell type in either a motile or non-motile form; motile cilia generate fluid flow needed for a variety of biological processes, such as left-right body patterning during development, while non-motile cilia serve as the signaling powerhouses of the cell, with vital singling receptors localized to their ciliary membranes. Much of the research currently available on Ca2+-dependent cellular actions and primary cilia are tissue-specific processes. However, basic stimuli-sensing pathways, such as mechanosensation, chemosensation, and electrical sensation (electrosensation), are complex processes entangled in many intersecting pathways; an overview of proposed functions involving cilia and Ca2+ interplay will be briefly summarized here. Next, we will focus on summarizing the evidence for their interactions in basic cellular activities, including the cell cycle, cell polarity and migration, neuronal pattering, glucose-mediated insulin secretion, biliary regulation, and bone formation. Literature investigating the role of cilia and Ca2+-dependent processes at a single-cellular level appears to be scarce, though overlapping signaling pathways imply that cilia and Ca2+ interact with each other on this level in widespread and varied ways on a perpetual basis. Vastly different cellular functions across many different cell types depend on context-specific Ca2+ and cilia interactions to trigger the correct physiological responses, and abnormalities in these interactions, whether at the tissue or the single-cell level, can result in diseases known as ciliopathies; due to their clinical relevance, pathological alterations of cilia function and Ca2+ signaling will also be briefly touched upon throughout this review.
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Affiliation(s)
| | | | - Wissam AbouAlaiwi
- Department of Pharmacology and Experimental Therapeutics, University of Toledo Health Science Campus, Toledo, OH 43614, USA; (H.S.); (S.L.)
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Schotthöfer SK, Bohrmann J. Bioelectrical and cytoskeletal patterns correlate with altered axial polarity in the follicular epithelium of the Drosophila mutant gurken. BMC DEVELOPMENTAL BIOLOGY 2020; 20:5. [PMID: 32169045 PMCID: PMC7071586 DOI: 10.1186/s12861-020-00210-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 02/26/2020] [Indexed: 01/08/2023]
Abstract
Background Bioelectrical signals are known to be involved in the generation of cell and tissue polarity as well as in cytoskeletal dynamics. The epithelium of Drosophila ovarian follicles is a suitable model system for studying connections between electrochemical gradients, patterns of cytoskeletal elements and axial polarity. By interactions between soma and germline cells, the transforming growth factor-α homolog Gurken (Grk) establishes both the anteroposterior and the dorsoventral axis during oogenesis. Results In the follicular epithelium of the wild-type (wt) and the polarity mutant grk, we analysed stage-specific gradients of membrane potentials (Vmem) and intracellular pH (pHi) using the potentiometric dye DiBAC4(3) and the fluorescent pH-indicator 5-CFDA,AM, respectively. In addition, we compared the cytoskeletal organisation in the follicular epithelium of wt and grk using fluorescent phalloidin and an antibody against acetylated α-tubulin. Corresponding to impaired polarity in grk, the slope of the anteroposterior Vmem-gradient in stage S9 is significantly reduced compared to wt. Even more striking differences in Vmem- and pHi-patterns become obvious during stage S10B, when the respective dorsoventral gradients are established in wt but not in grk. Concurrent with bioelectrical differences, wt and grk exhibit differences concerning cytoskeletal patterns in the follicular epithelium. During all vitellogenic stages, basal microfilaments in grk are characterised by transversal alignment, while wt-typical condensations in centripetal follicle cells (S9) and in dorsal centripetal follicle cells (S10B) are absent. Moreover, in grk, longitudinal alignment of microtubules occurs throughout vitellogenesis in all follicle cells, whereas in wt, microtubules in mainbody and posterior follicle cells exhibit a more cell-autonomous organisation. Therefore, in contrast to wt, the follicular epithelium in grk is characterised by missing or shallower electrochemical gradients and by more coordinated transcellular cytoskeletal patterns. Conclusions Our results show that bioelectrical polarity and cytoskeletal polarity are closely linked to axial polarity in both wt and grk. When primary polarity signals are altered, both bioelectrical and cytoskeletal patterns in the follicular epithelium change. We propose that not only cell-specific levels of Vmem and pHi, or the polarities of transcellular electrochemical gradients, but also the slopes of these gradients are crucial for cytoskeletal modifications and, thus, for proper development of epithelial polarity.
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Affiliation(s)
- Susanne Katharina Schotthöfer
- RWTH Aachen University, Institut für Biologie II, Abt. Zoologie und Humanbiologie, Worringerweg 3, 52056, Aachen, Germany
| | - Johannes Bohrmann
- RWTH Aachen University, Institut für Biologie II, Abt. Zoologie und Humanbiologie, Worringerweg 3, 52056, Aachen, Germany.
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15
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Cantero M, Gutierrez BC, Cantiello HF. Actin filaments modulate electrical activity of brain microtubule protein two‐dimensional sheets. Cytoskeleton (Hoboken) 2020; 77:167-177. [DOI: 10.1002/cm.21596] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 01/09/2020] [Accepted: 01/10/2020] [Indexed: 01/09/2023]
Affiliation(s)
- María Cantero
- Laboratorio de Canales IónicosInstituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, UNSE‐CONICET) Santiago del Estero Argentina
| | - Brenda C. Gutierrez
- Laboratorio de Canales IónicosInstituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, UNSE‐CONICET) Santiago del Estero Argentina
| | - Horacio F. Cantiello
- Laboratorio de Canales IónicosInstituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD, UNSE‐CONICET) Santiago del Estero Argentina
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16
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Investigation of the Electrical Properties of Microtubule Ensembles under Cell-Like Conditions. NANOMATERIALS 2020; 10:nano10020265. [PMID: 32033331 PMCID: PMC7075204 DOI: 10.3390/nano10020265] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 01/01/2023]
Abstract
Microtubules are hollow cylindrical polymers composed of the highly negatively-charged (~23e), high dipole moment (1750 D) protein α, β- tubulin. While the roles of microtubules in chromosomal segregation, macromolecular transport, and cell migration are relatively well-understood, studies on the electrical properties of microtubules have only recently gained strong interest. Here, we show that while microtubules at physiological concentrations increase solution capacitance, free tubulin has no appreciable effect. Further, we observed a decrease in electrical resistance of solution, with charge transport peaking between 20-60 Hz in the presence of microtubules, consistent with recent findings that microtubules exhibit electric oscillations at such low frequencies. We were able to quantify the capacitance and resistance of the microtubules (MT) network at physiological tubulin concentrations to be 1.27 × 10-5 F and 9.74 × 104 Ω. Our results show that in addition to macromolecular transport, microtubules also act as charge storage devices through counterionic condensation across a broad frequency spectrum. We conclude with a hypothesis of an electrically tunable cytoskeleton where the dielectric properties of tubulin are polymerisation-state dependent.
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Cantero MDR, Perez PL, Scarinci N, Cantiello HF. Two-Dimensional Brain Microtubule Structures Behave as Memristive Devices. Sci Rep 2019; 9:12398. [PMID: 31455820 PMCID: PMC6711987 DOI: 10.1038/s41598-019-48677-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 08/06/2019] [Indexed: 02/03/2023] Open
Abstract
Microtubules (MTs) are cytoskeletal structures that play a central role in a variety of cell functions including cell division and cargo transfer. MTs are also nonlinear electrical transmission lines that produce and conduct electrical oscillations elicited by changes in either electric field and/or ionic gradients. The oscillatory behavior of MTs requires a voltage-sensitive gating mechanism to enable the electrodiffusional ionic movement through the MT wall. Here we explored the electrical response of non-oscillating rat brain MT sheets to square voltage steps. To ascertain the nature of the possible gating mechanism, the electrical response of non-oscillating rat brain MT sheets (2D arrays of MTs) to square pulses was analyzed under voltage-clamping conditions. A complex voltage-dependent nonlinear charge movement was observed, which represented the summation of two events. The first contribution was a small, saturating, voltage-dependent capacitance with a maximum charge displacement in the range of 4 fC/μm2. A second, major contribution was a non-saturating voltage-dependent charge transfer, consistent with the properties of a multistep memristive device. The memristive capabilities of MTs could drive oscillatory behavior, and enable voltage-driven neuromorphic circuits and architectures within neurons.
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Affiliation(s)
- María Del Rocío Cantero
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD), UNSE-CONICET, El Zanjón, Santiago del Estero, Argentina.
| | - Paula L Perez
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD), UNSE-CONICET, El Zanjón, Santiago del Estero, Argentina
| | - Noelia Scarinci
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD), UNSE-CONICET, El Zanjón, Santiago del Estero, Argentina
| | - Horacio F Cantiello
- Laboratorio de Canales Iónicos, Instituto Multidisciplinario de Salud, Tecnología y Desarrollo (IMSaTeD), UNSE-CONICET, El Zanjón, Santiago del Estero, Argentina
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Facchin F, Canaider S, Tassinari R, Zannini C, Bianconi E, Taglioli V, Olivi E, Cavallini C, Tausel M, Ventura C. Physical energies to the rescue of damaged tissues. World J Stem Cells 2019; 11:297-321. [PMID: 31293714 PMCID: PMC6600852 DOI: 10.4252/wjsc.v11.i6.297] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/24/2019] [Accepted: 05/29/2019] [Indexed: 02/06/2023] Open
Abstract
Rhythmic oscillatory patterns sustain cellular dynamics, driving the concerted action of regulatory molecules, microtubules, and molecular motors. We describe cellular microtubules as oscillators capable of synchronization and swarming, generating mechanical and electric patterns that impact biomolecular recognition. We consider the biological relevance of seeing the inside of cells populated by a network of molecules that behave as bioelectronic circuits and chromophores. We discuss the novel perspectives disclosed by mechanobiology, bioelectromagnetism, and photobiomodulation, both in term of fundamental basic science and in light of the biomedical implication of using physical energies to govern (stem) cell fate. We focus on the feasibility of exploiting atomic force microscopy and hyperspectral imaging to detect signatures of nanomotions and electromagnetic radiation (light), respectively, generated by the stem cells across the specification of their multilineage repertoire. The chance is reported of using these signatures and the diffusive features of physical waves to direct specifically the differentiation program of stem cells in situ, where they already are resident in all the tissues of the human body. We discuss how this strategy may pave the way to a regenerative and precision medicine without the needs for (stem) cell or tissue transplantation. We describe a novel paradigm based upon boosting our inherent ability for self-healing.
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Affiliation(s)
- Federica Facchin
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), School of Medicine, University of Bologna, Bologna 40100, Italy
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Silvia Canaider
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), School of Medicine, University of Bologna, Bologna 40100, Italy
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Riccardo Tassinari
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Chiara Zannini
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Eva Bianconi
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Valentina Taglioli
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Elena Olivi
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | - Claudia Cavallini
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
| | | | - Carlo Ventura
- Department of Experimental, Diagnostic and Specialty Medicine (DIMES), School of Medicine, University of Bologna, Bologna 40100, Italy
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems, CNR, Bologna 40100, Italy
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Nonlinear calcium ion waves along actin filaments control active hair–bundle motility. Biosystems 2018; 173:181-190. [DOI: 10.1016/j.biosystems.2018.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Revised: 08/15/2018] [Accepted: 08/16/2018] [Indexed: 11/20/2022]
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Bundles of Brain Microtubules Generate Electrical Oscillations. Sci Rep 2018; 8:11899. [PMID: 30093720 PMCID: PMC6085364 DOI: 10.1038/s41598-018-30453-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 07/26/2018] [Indexed: 12/17/2022] Open
Abstract
Microtubules (MTs) are long cylindrical structures of the cytoskeleton that control cell division, intracellular transport, and the shape of cells. MTs also form bundles, which are particularly prominent in neurons, where they help define axons and dendrites. MTs are bio-electrochemical transistors that form nonlinear electrical transmission lines. However, the electrical properties of most MT structures remain largely unknown. Here we show that bundles of brain MTs spontaneously generate electrical oscillations and bursts of electrical activity similar to action potentials. Under intracellular-like conditions, voltage-clamped MT bundles displayed electrical oscillations with a prominent fundamental frequency at 39 Hz that progressed through various periodic regimes. The electrical oscillations represented, in average, a 258% change in the ionic conductance of the MT structures. Interestingly, voltage-clamped membrane-permeabilized neurites of cultured mouse hippocampal neurons were also capable of both, generating electrical oscillations, and conducting the electrical signals along the length of the structure. Our findings indicate that electrical oscillations are an intrinsic property of brain MT bundles, which may have important implications in the control of various neuronal functions, including the gating and regulation of cytoskeleton-regulated excitable ion channels and electrical activity that may aid and extend to higher brain functions such as memory and consciousness.
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Mousavidoust S, Mobasheri H, Riazi GH. Effects of static magnetic fields on the structure, polymerization, and bioelectric of tubulin assemblies. J Biomol Struct Dyn 2016; 35:3370-3383. [PMID: 27794634 DOI: 10.1080/07391102.2016.1254683] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Due to widespread exposure of human being to various sources of static magnetic fields (SMF), their effect on the spatial and temporal status of structure, arrangement, and polymerization of tubulin was studied at the molecular level. The intrinsic fluorescence intensity of tubulin was increased by SMF, indicating the repositioning of tryptophan and tyrosine residues. Circular Dichroism spectroscopy revealed variations in the ratios of alpha helix, beta, and random coil structures of tubulin as a result of exposure to SMF at 100, 200, and 300 mT. Transmission Electron microscopy of microtubules showed breaches and curvatures whose risk of occurrence increased as a function of field strength. Dynamic light scattering revealed an increase in the surface potential of tubulin aggregates exposed to SMF. The rate and extent of polymerization increased by 9.8 and 33.8%, at 100 and 300 mT, respectively, but decreased by 36.16% at 200 mT. The conductivity of polymerized tubulin increased in the presence of 100 and 300 mT SMF but remained the same as the control at 200 mT. The analysis of flexible amino acids along the sequence of tubulin revealed higher SMF susceptibility in the helical electron conduction pathway set through histidines rather than the vertical electron conduction pathway formed by tryptophan residues. The results reveal structural and functional effects of SMF on tubulin assemblies and microtubules that can be considered as a potential means to address the safety issues and for manipulation of bioelectrical characteristics of cytosol, intracellular trafficking and thus, the living status of cells, remotely.
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Affiliation(s)
- Sarah Mousavidoust
- a Laboratory of Membrane Biophysics & Macromolecule, Institute of Biochemistry and Biophysics (IBB) , University of Tehran , Tehran , Iran
| | - Hamid Mobasheri
- a Laboratory of Membrane Biophysics & Macromolecule, Institute of Biochemistry and Biophysics (IBB) , University of Tehran , Tehran , Iran.,b Biomaterial Research Center (BRC) , University of Tehran , Tehran , Iran
| | - Gholam Hossein Riazi
- c Laboratory of Bioorganics , Institute of Biochemistry and Biophysics (IBB), University of Tehran , Tehran , Iran
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