1
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Hughes MP. The cellular zeta potential: cell electrophysiology beyond the membrane. Integr Biol (Camb) 2024; 16:zyae003. [PMID: 38291769 DOI: 10.1093/intbio/zyae003] [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: 09/21/2023] [Revised: 12/16/2023] [Accepted: 01/06/2024] [Indexed: 02/01/2024]
Abstract
The standard model of the cell membrane potential Vm describes it as arising from diffusion currents across a membrane with a constant electric field, with zero electric field outside the cell membrane. However, the influence of Vm has been shown to extend into the extracellular space where it alters the cell's ζ-potential, the electrical potential measured a few nm from the cell surface which defines how the cell interacts with charged entities in its environment, including ions, molecules, and other cells. The paradigm arising from surface science is that the ζ-potential arises only from fixed membrane surface charge, and has consequently received little interest. However, if the ζ-potential can mechanistically and dynamically change by alteration of Vm, it allows the cell to dynamically alter cell-cell and cell-molecule interactions and may explain previously unexplained electrophysiological behaviours. Whilst the two potentials Vm and ζ are rarely reported together, they are occasionally described in different studies for the same cell type. By considering published data on these parameters across multiple cell types, as well as incidences of unexplained but seemingly functional Vm changes correlating with changes in cell behaviour, evidence is presented that this may play a functional role in the physiology of red blood cells, macrophages, platelets, sperm, ova, bacteria and cancer. Understanding how these properties will improve understanding of the role of electrical potentials and charges in the regulation of cell function and in the way in which cells interact with their environment. Insight The zeta (ζ) potential is the electrical potential a few nm beyond the surface of any suspensoid in water. Whilst typically assumed to arise only from fixed charges on the cell surface, recent and historical evidence shows a strong link to the cell's membrane potential Vm, which the cell can alter mechanistically through the use of ion channels. Whilst these two potentials have rarely been studied simultaneously, this review collates data across multiple studies reporting Vm, ζ-potential, electrical properties of changes in cell behaviour. Collectively, this points to Vm-mediated ζ-potential playing a significant role in the physiology and activity of blood cells, immune response, developmental biology and egg fertilization, and cancer among others.
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Affiliation(s)
- Michael Pycraft Hughes
- Department of Biomedical Engineering/Healthcare Engineering Innovation Centre (HEIC), Khalifa University, Abu Dhabi, UAE
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2
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Yu X, Mukwaya V, Mann S, Dou H. Signal Transduction in Artificial Cells. SMALL METHODS 2023; 7:e2300231. [PMID: 37116092 DOI: 10.1002/smtd.202300231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/06/2023] [Indexed: 06/19/2023]
Abstract
In recent years, significant progress has been made in the emerging field of constructing biomimetic soft compartments with life-like behaviors. Given that biological activities occur under a flux of energy and matter exchange, the implementation of rudimentary signaling pathways in artificial cells (protocells) is a prerequisite for the development of adaptive sense-response phenotypes in cytomimetic models. Herein, recent approaches to the integration of signal transduction modules in model protocells prepared by bottom-up construction are discussed. The approaches are classified into two categories involving invasive biochemical signals or non-invasive physical stimuli. In the former mechanism, transducers with intrinsic recognition capability respond with high specificity, while in the latter, artificial cells respond through intra-protocellular energy transduction. Although major challenges remain in the pursuit of a sophisticated artificial signaling network for the orchestration of higher-order cytomimetic models, significant advances have been made in establishing rudimentary protocell communication networks, providing novel organizational models for the development of life-like microsystems and new avenues in protoliving technologies.
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Affiliation(s)
- Xiaolei Yu
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
- Zhangjiang Institute for Advanced Study (ZIAS), Shanghai Jiao Tong University, Shanghai, 201203, China
| | - Vincent Mukwaya
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
- Zhangjiang Institute for Advanced Study (ZIAS), Shanghai Jiao Tong University, Shanghai, 201203, China
| | - Stephen Mann
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
- Zhangjiang Institute for Advanced Study (ZIAS), Shanghai Jiao Tong University, Shanghai, 201203, China
- Max Planck Bristol Centre for Minimal Biology and Centre for Protolife Research, School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK
| | - Hongjing Dou
- State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China
- Zhangjiang Institute for Advanced Study (ZIAS), Shanghai Jiao Tong University, Shanghai, 201203, China
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3
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Perelman RT, Schmidt A, Khan U, Walter NG. Spontaneous Confinement of mRNA Molecules at Biomolecular Condensate Boundaries. Cells 2023; 12:2250. [PMID: 37759470 PMCID: PMC10526803 DOI: 10.3390/cells12182250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/01/2023] [Accepted: 09/09/2023] [Indexed: 09/29/2023] Open
Abstract
Cellular biomolecular condensates, termed ribonucleoprotein (RNP) granules, are often enriched in messenger RNA (mRNA) molecules relative to the surrounding cytoplasm. Yet, the spatial localization and diffusion of mRNAs in close proximity to phase separated RNP granules are not well understood. In this study, we performed single-molecule fluorescence imaging experiments of mRNAs in live cells in the presence of two types of RNP granules, stress granules (SGs) and processing bodies (PBs), which are distinct in their molecular composition and function. We developed a photobleaching- and noise-corrected colocalization imaging algorithm that was employed to determine the accurate positions of individual mRNAs relative to the granule's boundaries. We found that mRNAs are often localized at granule boundaries, an observation consistent with recently published data. We suggest that mRNA molecules become spontaneously confined at the RNP granule boundary similar to the adsorption of polymer molecules at liquid-liquid interfaces, which is observed in various technological and biological processes. We also suggest that this confinement could be due to a combination of intermolecular interactions associated with, first, the screening of a portion of the RNP granule interface by the polymer and, second, electrostatic interactions due to a strong electric field induced by a Donnan potential generated across the thin interface.
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Affiliation(s)
- Rebecca T. Perelman
- Single Molecule Analysis Group, University of Michigan, Ann Arbor, MI 48109, USA; (R.T.P.); (A.S.)
| | - Andreas Schmidt
- Single Molecule Analysis Group, University of Michigan, Ann Arbor, MI 48109, USA; (R.T.P.); (A.S.)
| | - Umar Khan
- Center for Advanced Biomedical Imaging and Photonics, Beth Israel Deaconess Medical Center, Harvard University, Boston, MA 02115, USA;
| | - Nils G. Walter
- Single Molecule Analysis Group, University of Michigan, Ann Arbor, MI 48109, USA; (R.T.P.); (A.S.)
- Center for RNA Biomedicine, Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA
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4
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Huynh PK, Nguyen D, Binder G, Ambardar S, Le TQ, Voronine DV. Multifractality in Surface Potential for Cancer Diagnosis. J Phys Chem B 2023; 127:6867-6877. [PMID: 37525377 DOI: 10.1021/acs.jpcb.3c01733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Recent advances in high-resolution biomedical imaging have improved cancer diagnosis, focusing on morphological, electrical, and biochemical properties of cells and tissues, scaling from cell clusters down to the molecular level. Multiscale imaging revealed high complexity that requires advanced data processing methods of multifractal analysis. We performed label-free multiscale imaging of surface potential variations in human ovarian cancer cells using Kelvin probe force microscopy (KPFM). An improvement in the differentiation between nonmalignant and cancerous cells by multifractal analysis using adaptive versus median threshold for image binarization was demonstrated. The results reveal the multifractality of cancer cells as a new biomarker for cancer diagnosis.
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Affiliation(s)
- Phat K Huynh
- Department of Industrial and Management Systems Engineering, University of South Florida, Tampa, Florida 33620, United States
| | - Dang Nguyen
- Department of Medical Engineering, University of South Florida, Tampa, Florida 33620, United States
| | - Grace Binder
- Department of Chemistry, University of South Florida, Tampa, Florida 33620, United States
| | - Sharad Ambardar
- Department of Medical Engineering, University of South Florida, Tampa, Florida 33620, United States
| | - Trung Q Le
- Department of Industrial and Management Systems Engineering, University of South Florida, Tampa, Florida 33620, United States
- Department of Medical Engineering, University of South Florida, Tampa, Florida 33620, United States
| | - Dmitri V Voronine
- Department of Medical Engineering, University of South Florida, Tampa, Florida 33620, United States
- Department of Physics, University of South Florida, Tampa, Florida 33620, United States
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Průša J, Cifra M. Electro-detachment of kinesin motor domain from microtubule in silico. Comput Struct Biotechnol J 2023; 21:1349-1361. [PMID: 36814722 PMCID: PMC9939557 DOI: 10.1016/j.csbj.2023.01.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 01/15/2023] [Accepted: 01/15/2023] [Indexed: 01/22/2023] Open
Abstract
Kinesin is a motor protein essential in cellular functions, such as intracellular transport and cell-division, as well as for enabling nanoscopic transport in bio-nanotechnology. Therefore, for effective control of function for nanotechnological applications, it is important to be able to modify the function of kinesin. To circumvent the limitations of chemical modifications, here we identify another potential approach for kinesin control: the use of electric forces. Using full-atom molecular dynamics simulations (247,358 atoms, total time ∼ 4.4 μs), we demonstrate, for the first time, that the kinesin-1 motor domain can be detached from a microtubule by an intense electric field within the nanosecond timescale. We show that this effect is field-direction dependent and field-strength dependent. A detailed analysis of the electric forces and the work carried out by electric field acting on the microtubule-kinesin system shows that it is the combined action of the electric field pulling on the β-tubulin C-terminus and the electric-field-induced torque on the kinesin dipole moment that causes kinesin detachment from the microtubule. It is shown, for the first time in a mechanistic manner, that an electric field can dramatically affect molecular interactions in a heterologous functional protein assembly. Our results contribute to understanding of electromagnetic field-biomatter interactions on a molecular level, with potential biomedical and bio-nanotechnological applications for harnessing control of protein nanomotors.
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Funk RHW, Scholkmann F. The significance of bioelectricity on all levels of organization of an organism. Part 1: From the subcellular level to cells. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2023; 177:185-201. [PMID: 36481271 DOI: 10.1016/j.pbiomolbio.2022.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/24/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022]
Abstract
Bioelectricity plays an essential role in the structural and functional organization of biological organisms. In this first article of our three-part series, we summarize the importance of bioelectricity for the basic structural level of biological organization, i.e. from the subcellular level (charges, ion channels, molecules and cell organelles) to cells.
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Affiliation(s)
- Richard H W Funk
- Institute of Anatomy, Center for Theoretical Medicine, TU-Dresden, 01307, Dresden, Germany; Dresden International University, 01067, Dresden, Germany.
| | - Felix Scholkmann
- Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, 8091, Zurich, Switzerland.
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Hughes MP, Fry CH, Labeed FH. Cytoplasmic anion/cation imbalances applied across the membrane capacitance may form a significant component of the resting membrane potential of red blood cells. Sci Rep 2022; 12:15005. [PMID: 36056086 PMCID: PMC9440063 DOI: 10.1038/s41598-022-19316-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 08/26/2022] [Indexed: 11/24/2022] Open
Abstract
Electrical aspects of cell function manifest in many ways. The most widely studied is the cell membrane potential, Vm, but others include the conductance and capacitance of the membrane, the conductance of the enclosed cytoplasm, as well as the charge at the cell surface (an electrical double layer) producing an extracellular electrical potential, the ζ-potential. Empirical relationships have been identified between many of these, but not the mechanisms that link them all. Here we examine relationships between Vm and the electrical conductivities of both the cytoplasm and extracellular media, using data from a suspensions of red blood cells. We have identified linear relationships between extracellular medium conductivity, cytoplasm conductivity and Vm. This is in contrast to the standard model of a resting membrane potential which describes a logarithmic relationship between Vm and the concentration of permeable ions in the extracellular medium. The model here suggests that Vm is partially electrostatic in origin, arising from a charge imbalance at an inner electrical double-layer, acting across the membrane and double-layer capacitances to produce a voltage. This model describes an origin for coupling between Vm and ζ, by which cells can alter their electrostatic relationship with their environment, with implications for modulation of membrane ion transport, adhesion of proteins such as antibodies and wider cell-cell interactions.
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Affiliation(s)
- Michael Pycraft Hughes
- Department of Biomedical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates.
- Centre for Biomedical Engineering, University of Surrey, Guildford, GU2 7XH, Surrey, UK.
| | - Christopher H Fry
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, BS8 1TD, UK
| | - Fatima H Labeed
- Centre for Biomedical Engineering, University of Surrey, Guildford, GU2 7XH, Surrey, UK
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8
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Liu Z, Chen J, Bai Q, Lin YN, Liang D. Coacervate Formed by an ATP-Binding Aptamer and Its Dynamic Behavior under Nonequilibrium Conditions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:6425-6434. [PMID: 35543367 DOI: 10.1021/acs.langmuir.2c00580] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Although numerous protocell models have been developed to explore the possible pathway of the origin of life on the early earth, few truly fulfill the roles of the DNA/RNA sequence and ATP molecules, which are keys to cell replication and evolution. The ATP-binding aptamer offers an opportunity to combine sequence and energy molecules. In this work, we choose the coacervate droplet as the protocell model and investigate the interaction of the DNA aptamer, poly(l-lysine)(PLL), and ATP under varying conditions. PLL and aptamers form solid precipitates, which spontaneously transform to coacervate droplets as ATP is introduced. The selective uptake and sequestration of exogenous molecules is achieved by the ATP-containing coacervates. As an electric field is applied to expel ATP, the portion of the droplet deficient in ATP becomes solid. The solid/liquid phase ratio is tunable by varying the electric field strength and excitation time. Together with the vacuolization process, a solid head with a soft mouth periodically opening and closing is created. Moreover, the composite coacervate droplet gradually grows as it is treated with an electric field and cannot recover to the original liquid phase after the power is turned off and replenished with ATP. Our work highlights that the proper integration of the DNA sequence, ATP, and energy input could be a powerful strategy for creating a protocell with certain living features.
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Affiliation(s)
- Zhijun Liu
- Beijing National Laboratory for Molecular Sciences, Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Jiaxin Chen
- Beijing National Laboratory for Molecular Sciences, Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Qingwen Bai
- Beijing National Laboratory for Molecular Sciences, Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Ya-Nan Lin
- Beijing National Laboratory for Molecular Sciences, Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Dehai Liang
- Beijing National Laboratory for Molecular Sciences, Department of Polymer Science and Engineering and the Key Laboratory of Polymer Chemistry and Physics of the Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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9
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Chierici F, Dogariu A, Tuszynski JA. Computational Investigation of the Ordered Water System Around Microtubules: Implications for Protein Interactions. Front Mol Biosci 2022; 9:884043. [PMID: 35547397 PMCID: PMC9083000 DOI: 10.3389/fmolb.2022.884043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/05/2022] [Indexed: 11/17/2022] Open
Abstract
The existence of an exclusion zone in which particles of a colloidal suspension in water are repelled from hydrophilic surfaces has been experimentally demonstrated in numerous studies, especially in the case of Nafion surfaces. Various explanations have been proposed for the origin of this phenomenon, which is not completely understood yet. In particular, the existence of a fourth phase of water has been proposed by G. Pollack and if this theory is proven correct, its implications on our understanding of the properties of water, especially in biological systems, would be profound and could give rise to new medical therapies. Here, a simple approach based on the linearized Poisson-Boltzmann equation is developed in order to study the repulsive forces mediated by ordered water and involving the following interacting biomolecules: 1) microtubule and a tubulin dimer, 2) two tubulin dimers and 3) a tubulin sheet and a tubulin dimer. The choice of microtubules in this study is motivated because they could be a good candidate for the generation of an exclusion zone in the cell and these models could be a starting point for detailed experimental investigations of this phenomenon.
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Affiliation(s)
- Francesco Chierici
- DIMEAS, Politecnico di Torino, Torino, Italy
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, United States
- *Correspondence: Francesco Chierici,
| | - Aristide Dogariu
- CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, United States
| | - Jack A. Tuszynski
- DIMEAS, Politecnico di Torino, Torino, Italy
- Department of Physics, University of Alberta, Edmonton, AB, Canada
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10
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Gagkayeva ZV, Gorshunov BP, Kachesov AY, Motovilov KA. Infrared fingerprints of water collective dynamics indicate proton transport in biological systems. Phys Rev E 2022; 105:044409. [PMID: 35590571 DOI: 10.1103/physreve.105.044409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 04/03/2022] [Indexed: 06/15/2023]
Abstract
Recent publications on spectroscopy of water layers in water bridge structures revealed a significant enhancement of the proton mobility and the dielectric contribution of translational vibrations of water molecules in the interfacial layers compared to bulk water. Herewith, the results of long-term studies of proton dynamics in solid-state acids have shown that proton mobility increases significantly with the predominance of hydronium, but not Zundel, cations in the aqueous phase. In the present work, in the light of these data, we reanalyzed our previously published results on broadband dielectric spectroscopy of bovine heart cytochrome c, bovine serum albumin, and the extracellular matrix and filaments of Shewanella oneidensis MR-1. We revealed that, just as in water bridges, an increase in electrical conductivity in these systems correlates with an increase in the dielectric contribution of water molecular translational vibrations. In addition, the appearance of spectral signatures of the hydronium cations was observed only in those cases when the system revealed noticeable electrical conductivity due to delocalized charge carriers.
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Affiliation(s)
- Z V Gagkayeva
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology (National Research University), 9 Institutskiy per., Dolgoprudny, Moscow Region 141701, Russian Federation
| | - B P Gorshunov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology (National Research University), 9 Institutskiy per., Dolgoprudny, Moscow Region 141701, Russian Federation
| | - A Ye Kachesov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology (National Research University), 9 Institutskiy per., Dolgoprudny, Moscow Region 141701, Russian Federation
| | - K A Motovilov
- Center for Photonics and 2D Materials, Moscow Institute of Physics and Technology (National Research University), 9 Institutskiy per., Dolgoprudny, Moscow Region 141701, Russian Federation
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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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12
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Tassinari R, Cavallini C, Olivi E, Taglioli V, Zannini C, Ventura C. Unveiling the morphogenetic code: A new path at the intersection of physical energies and chemical signaling. World J Stem Cells 2021; 13:1382-1393. [PMID: 34786150 PMCID: PMC8567452 DOI: 10.4252/wjsc.v13.i10.1382] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/16/2021] [Accepted: 09/10/2021] [Indexed: 02/06/2023] Open
Abstract
In this editorial, we discuss the remarkable role of physical energies in the control of cell signaling networks and in the specification of the architectural plan of both somatic and stem cells. In particular, we focus on the biological relevance of bioelectricity in the pattern control that orchestrates both developmental and regenerative pathways. To this end, the narrative starts from the dawn of the first studies on animal electricity, reconsidering the pioneer work of Harold Saxton Burr in the light of the current achievements. We finally discuss the most recent evidence showing that bioelectric signaling is an essential component of the informational processes that control pattern specification during embryogenesis, regeneration, or even malignant transformation. We conclude that there is now mounting evidence for the existence of a Morphogenetic Code, and that deciphering this code may lead to unprecedented opportunities for the development of novel paradigms of cure in regenerative and precision medicine.
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Affiliation(s)
- Riccardo Tassinari
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems – ELDOR LAB, Bologna 40129, Italy
| | - Claudia Cavallini
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems – ELDOR LAB, Bologna 40129, Italy
| | - Elena Olivi
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems – ELDOR LAB, Bologna 40129, Italy
| | - Valentina Taglioli
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems – ELDOR LAB, Bologna 40129, Italy
| | - Chiara Zannini
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems – ELDOR LAB, Bologna 40129, Italy
| | - Carlo Ventura
- National Laboratory of Molecular Biology and Stem Cell Engineering, National Institute of Biostructures and Biosystems – ELDOR LAB, Bologna 40129, Italy
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13
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The SARS-CoV-2 spike protein is vulnerable to moderate electric fields. Nat Commun 2021; 12:5407. [PMID: 34518528 PMCID: PMC8437970 DOI: 10.1038/s41467-021-25478-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 08/12/2021] [Indexed: 12/23/2022] Open
Abstract
Most of the ongoing projects aimed at the development of specific therapies and vaccines against COVID-19 use the SARS-CoV-2 spike (S) protein as the main target. The binding of the spike protein with the ACE2 receptor (ACE2) of the host cell constitutes the first and key step for virus entry. During this process, the receptor binding domain (RBD) of the S protein plays an essential role, since it contains the receptor binding motif (RBM), responsible for the docking to the receptor. So far, mostly biochemical methods are being tested in order to prevent binding of the virus to ACE2. Here we show, with the help of atomistic simulations, that external electric fields of easily achievable and moderate strengths can dramatically destabilise the S protein, inducing long-lasting structural damage. One striking field-induced conformational change occurs at the level of the recognition loop L3 of the RBD where two parallel beta sheets, believed to be responsible for a high affinity to ACE2, undergo a change into an unstructured coil, which exhibits almost no binding possibilities to the ACE2 receptor. We also show that these severe structural changes upon electric-field application also occur in the mutant RBDs corresponding to the variants of concern (VOC) B.1.1.7 (UK), B.1.351 (South Africa) and P.1 (Brazil). Remarkably, while the structural flexibility of S allows the virus to improve its probability of entering the cell, it is also the origin of the surprising vulnerability of S upon application of electric fields of strengths at least two orders of magnitude smaller than those required for damaging most proteins. Our findings suggest the existence of a clean physical method to weaken the SARS-CoV-2 virus without further biochemical processing. Moreover, the effect could be used for infection prevention purposes and also to develop technologies for in-vitro structural manipulation of S. Since the method is largely unspecific, it can be suitable for application to other mutations in S, to other proteins of SARS-CoV-2 and in general to membrane proteins of other virus types. The SARS-CoV-2 Spike protein is essential for viral infectivity and binds to the host receptor ACE2. Here, the authors present MD simulations of the Spike protein and its variants of concern and observe that the Spike protein is destabilised by moderate static electric fields, and undergoes field-induced conformational changes that hinder binding to ACE2.
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Development of an Electroactive Hydrogel as a Scaffold for Excitable Tissues. Int J Biomater 2021; 2021:6669504. [PMID: 33603789 PMCID: PMC7868160 DOI: 10.1155/2021/6669504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 01/15/2021] [Accepted: 01/21/2021] [Indexed: 01/07/2023] Open
Abstract
For many cells used in tissue engineering applications, the scaffolds upon which they are seeded do not entirely mimic their native environment, particularly in the case of excitable tissues. For instance, muscle cells experience contraction and relaxation driven by the electrical input of an action potential. Electroactive materials can also deform in response to electrical input; however, few such materials are currently suitable as cell scaffolds. We previously described the development of poly(ethyelene glycol) diacrylate-poly(acrylic acid) as an electroactive scaffold. Although the scaffold itself supported cell growth and attachment, the voltage (20 V) required to actuate these scaffolds was cytotoxic. Here, we describe the further development of our hydrogels into scaffolds capable of actuation at voltages (5 V) that were not cytotoxic to seeded cells. This study describes the critical next steps towards the first functional electroactive tissue engineering scaffold.
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Calvo P, Baluška F, Trewavas A. Integrated information as a possible basis for plant consciousness. Biochem Biophys Res Commun 2020; 564:158-165. [PMID: 33081970 DOI: 10.1016/j.bbrc.2020.10.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 09/23/2020] [Accepted: 10/09/2020] [Indexed: 12/29/2022]
Abstract
It is commonly assumed that plants do not possess consciousness. Since the criterion for this assumption is usually human consciousness this assumption represents a top down attitude. It is obvious that plants are not animals and using animal criteria of consciousness will lead to its rejection in plants. However using a bottom up evolutionary approach and a leading theory of consciousness, Integrated Information Theory, we report that we find evidence that indicates that plant meristems act in a conscious fashion although probably at the level of minimal consciousness. Since many plants contain multiple meristems these observations highlight a very different evolutionary approach to consciousness in biological organisms.
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Affiliation(s)
- Paco Calvo
- Minimal Intelligence Laboratory, Universidad de Murcia, Murcia, Spain.
| | - František Baluška
- Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany
| | - Anthony Trewavas
- Institute of Molecular Plant Science, Kings Buildings, University of Edinburgh, Edinburgh, Scotland, United Kingdom
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16
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Benarroch JM, Asally M. The Microbiologist’s Guide to Membrane Potential Dynamics. Trends Microbiol 2020; 28:304-314. [DOI: 10.1016/j.tim.2019.12.008] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/25/2019] [Accepted: 12/09/2019] [Indexed: 10/25/2022]
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17
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Lin Y, Jing H, Liu Z, Chen J, Liang D. Dynamic Behavior of Complex Coacervates with Internal Lipid Vesicles under Nonequilibrium Conditions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:1709-1717. [PMID: 32004005 DOI: 10.1021/acs.langmuir.9b03561] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
During the evolution of life on earth, the emergence of lipid membrane-bounded compartments is one of the most enigmatic events. Endosymbiosis has been hypothesized as one of the solutions. In this work, using a coacervate droplet formed by single-stranded oligonucleotides (ss-oligo) and poly(l-lysine) (PLL) as the protocell model, we monitored the uptake of liposomes of different types and studied the dynamic behavior of the resulting composite droplet under the electric field. The coacervate droplet exhibits affinity for the liposomes of varying charges. However, the permeation of liposome is also controlled by electrostatic interactions. Dominated by electrostatic attraction, the positively charged liposome is retained inside the droplet as growing fibrous structures, while the negatively charged liposome is mainly coated on the droplet surface. Permeation and even distribution occur when the liposome and the droplet carry the same charges, or at least one of them is neutral. As an electric field is applied to trigger repetitive cycles of vacuolization in the ss-oligo/PLL droplet, the fibrous structure formed by the positively charged liposome is basically intact, while a new phase is generated together with uneven mass transport as the negatively charged liposome is internalized. Interestingly, the release of daughter droplets with similar components occurs on the droplet containing neutral liposomes. Our work not only provides a step toward creating protocells with hierarchical structures and biofunctions using a biogenetic material via simple mixing but also sheds light on the possible origin of the lipid structure inside a living organism.
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Affiliation(s)
- Ya'nan Lin
- Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Hairong Jing
- Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Zhijun Liu
- Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Jiaxin Chen
- Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Dehai Liang
- Beijing National Laboratory for Molecular Sciences and the Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
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18
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19
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della Valle E, Marracino P, Pakhomova O, Liberti M, Apollonio F. Nanosecond pulsed electric signals can affect electrostatic environment of proteins below the threshold of conformational effects: The case study of SOD1 with a molecular simulation study. PLoS One 2019; 14:e0221685. [PMID: 31454403 PMCID: PMC6711501 DOI: 10.1371/journal.pone.0221685] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Accepted: 08/13/2019] [Indexed: 12/19/2022] Open
Abstract
Electric fields can be a powerful tool to interact with enzymes or proteins, with an intriguing perspective to allow protein manipulation. Recently, researchers have focused the interest on intracellular enzyme modifications triggered by the application of nanosecond pulsed electric fields. These findings were also supported by theoretical predictions from molecular dynamics simulations focussing on significant variations in protein secondary structures. In this work, a theoretical study utilizing molecular dynamics simulations is proposed to explore effects of electric fields of high intensity and very short nanosecond duration applied to the superoxide dismutase (Cu/Zn-SOD or SOD-1), an important enzyme involved in the cellular antioxidant defence mechanism. The effects of 100-nanosecond pulsed electric fields, with intensities ranging from 108 to 7x108 V/m, on a single SOD1 enzyme are presented. We demonstrated that the lowest intensity of 108 V/m, although not inducing structural changes, can produce electrostatic modifications on the reaction centre of the enzyme, as apparent from the dipolar response and the electric field distribution of the protein active site. Electric pulses above 5x108 V/m produced a fast transition between the folded and a partially denatured state, as inferred by the secondary structures analysis. Finally, for the highest field intensity used (7x108 V/m), a not reversible transition toward an unfolded state was observed.
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Affiliation(s)
- Elena della Valle
- BioElectronic Vision Lab, University of Michigan, Ann Arbor, Michigan, United States of America
| | | | - Olga Pakhomova
- Frank Reidy Research Center for Bioelectrics, Old Dominion University, Norfolk, Virginia, United States of America
| | - Micaela Liberti
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome, Italy
| | - Francesca Apollonio
- Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Rome, Italy
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20
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Barvitenko N, Lawen A, Aslam M, Pantaleo A, Saldanha C, Skverchinskaya E, Regolini M, Tuszynski JA. Integration of intracellular signaling: Biological analogues of wires, processors and memories organized by a centrosome 3D reference system. Biosystems 2018; 173:191-206. [PMID: 30142359 DOI: 10.1016/j.biosystems.2018.08.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 08/03/2018] [Accepted: 08/20/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Myriads of signaling pathways in a single cell function to achieve the highest spatio-temporal integration. Data are accumulating on the role of electromechanical soliton-like waves in signal transduction processes. Theoretical studies strongly suggest feasibility of both classical and quantum computing involving microtubules. AIM A theoretical study of the role of the complex composed of the plasma membrane and the microtubule-based cytoskeleton as a system that transmits, stores and processes information. METHODS Theoretical analysis presented here refers to (i) the Penrose-Hameroff theory of consciousness (Orchestrated Objective Reduction; Orch OR), (ii) the description of the centrosome as a reference system for construction of the 3D map of the cell proposed by Regolini, (iii) the Heimburg-Jackson model of the nerve pulse propagation along axons' lipid bilayer as soliton-like electro-mechanical waves. RESULTS AND CONCLUSION The ideas presented in this paper provide a qualitative model for the decision-making processes in a living cell undergoing a differentiation process. OUTLOOK This paper paves the way for the real-time live-cell observation of information processing by microtubule-based cytoskeleton and cell fate decision making.
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Affiliation(s)
| | - Alfons Lawen
- Monash University, School of Biomedical Sciences, Department of Biochemistry and Molecular Biology, VIC, 3800, Australia
| | - Muhammad Aslam
- Medical Clininc I, Cardiology/Angiology, University Hospital, Justus-Liebig-University, Giessen, Germany
| | - Antonella Pantaleo
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Carlota Saldanha
- Instituto de Medicina Molecular, Instituto de Bioquimica, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | | | - Marco Regolini
- Department of Bioengineering and Mathematical Modeling, AudioLogic, Milan, Italy
| | - Jack A Tuszynski
- Department of Oncology, University of Alberta, Edmonton, Alberta, Canada; Department of Physics, University of Alberta, Edmonton, Alberta, Canada; Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, IT-10128, Torino, Italy.
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Rourk CJ. Ferritin and neuromelanin "quantum dot" array structures in dopamine neurons of the substantia nigra pars compacta and norepinephrine neurons of the locus coeruleus. Biosystems 2018; 171:48-58. [PMID: 30048795 DOI: 10.1016/j.biosystems.2018.07.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 07/13/2018] [Accepted: 07/22/2018] [Indexed: 01/28/2023]
Abstract
In this review, the author shows that ferritin has documented quantum dot material properties that have been reported in numerous independent studies, and can enable quantum mechanical electron transport over substantial distances. In addition, neuromelanin is a pi-conjugated polymer, and quantum dot/pi-conjugated polymer combinations have been reported in numerous independent studies to facilitate electron transport for solar photovoltaic and other applications. Both ferritin and neuromelanin are present in large quantities in the dopamine neurons of the substantia nigra pars compactaand the norepinephrine neurons of the locus coeruleus. The unique structure of subgroups of these neurons that have a large number of axon branches and synapses may have evolved to take advantage of this electron transport mechanism, if it is present, such as to coordinate conscious action, or for other purposes. Independent clinical and laboratory studies are also reviewed that corroborate this theory of coordinated action in these neuron groups. Research to validate the theory using charge transport measurements, materials characterization, existing fluorescent probe material and reaction time testing is proposed.
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22
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D'Agostino L. Native DNA electronics: is it a matter of nanoscale assembly? NANOSCALE 2018; 10:12268-12275. [PMID: 29946628 DOI: 10.1039/c8nr03153c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The genomic DNA is enveloped by nanotubes formed by the nuclear aggregates of polyamines (NAPs) that induce DNA conformational changes and provide protection and increased interaction abilities for the double strands. In a physiological environment, the nanotube arrangement is initiated by spontaneous interaction among the terminal amino groups of the polyamines and the phosphate ions, with the consequent formation of cyclic monomers that hook at the DNA grooves. The polymer thus formed has the morphological features of an organic semiconductor and therefore, it can be considered to be able to conduct electric charges. Phosphate ions positioned on the NAP external surface could regulate, as in a physical electric circuit, both linear and rotational (histones) protein motion, in accordance with the basilar principles of the electronics. A model of a carrier system for protein motion along the polymer wrapping the DNA strands, based on the phosphate-phosphate complexation, is proposed.
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23
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Tian B, Xu S, Rogers JA, Cestellos-Blanco S, Yang P, Carvalho-de-Souza JL, Bezanilla F, Liu J, Bao Z, Hjort M, Cao Y, Melosh N, Lanzani G, Benfenati F, Galli G, Gygi F, Kautz R, Gorodetsky AA, Kim SS, Lu TK, Anikeeva P, Cifra M, Krivosudský O, Havelka D, Jiang Y. Roadmap on semiconductor-cell biointerfaces. Phys Biol 2018; 15:031002. [PMID: 29205173 PMCID: PMC6599646 DOI: 10.1088/1478-3975/aa9f34] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This roadmap outlines the role semiconductor-based materials play in understanding the complex biophysical dynamics at multiple length scales, as well as the design and implementation of next-generation electronic, optoelectronic, and mechanical devices for biointerfaces. The roadmap emphasizes the advantages of semiconductor building blocks in interfacing, monitoring, and manipulating the activity of biological components, and discusses the possibility of using active semiconductor-cell interfaces for discovering new signaling processes in the biological world.
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Affiliation(s)
- Bozhi Tian
- Department of Chemistry, University of Chicago, Chicago, IL 60637, United States of America
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24
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Wenger C, Miranda PC, Salvador R, Thielscher A, Bomzon Z, Giladi M, Mrugala MM, Korshoej AR. A Review on Tumor-Treating Fields (TTFields): Clinical Implications Inferred From Computational Modeling. IEEE Rev Biomed Eng 2018; 11:195-207. [DOI: 10.1109/rbme.2017.2765282] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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25
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Van Meervelt V, Soskine M, Singh S, Schuurman-Wolters GK, Wijma HJ, Poolman B, Maglia G. Real-Time Conformational Changes and Controlled Orientation of Native Proteins Inside a Protein Nanoreactor. J Am Chem Soc 2017; 139:18640-18646. [PMID: 29206456 PMCID: PMC6150693 DOI: 10.1021/jacs.7b10106] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
![]()
Protein conformations play crucial
roles in most, if not all, biological
processes. Here we show that the current carried through a nanopore
by ions allows monitoring conformational changes of single and native
substrate-binding domains (SBD) of an ATP-Binding Cassette importer
in real-time. Comparison with single-molecule Förster Resonance
Energy Transfer and ensemble measurements revealed that proteins trapped
inside the nanopore have bulk-like properties. Two ligand-free and
two ligand-bound conformations of SBD proteins were inferred and their
kinetic constants were determined. Remarkably, internalized proteins
aligned with the applied voltage bias, and their orientation could
be controlled by the addition of a single charge to the protein surface.
Nanopores can thus be used to immobilize proteins on a surface with
a specific orientation, and will be employed as nanoreactors for single-molecule
studies of native proteins. Moreover, nanopores with internal protein
adaptors might find further practical applications in multianalyte
sensing devices.
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Affiliation(s)
- Veerle Van Meervelt
- Department of Chemistry, University of Leuven , Leuven B-3001, Belgium.,Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
| | - Misha Soskine
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
| | - Shubham Singh
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
| | - Gea K Schuurman-Wolters
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
| | - Hein J Wijma
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
| | - Bert Poolman
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
| | - Giovanni Maglia
- Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen , Groningen 9747 AG, The Netherlands
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26
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Ye H. Kinematic difference between a biological cell and an artificial vesicle in a strong DC electric field – a “shell” membrane model study. BMC BIOPHYSICS 2017. [DOI: 10.1186/s13628-017-0038-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Paulitsch-Fuchs AH, Zsohár A, Wexler AD, Zauner A, Kittinger C, de Valença J, Fuchs EC. Behavioral study of selected microorganisms in an aqueous electrohydrodynamic liquid bridge. Biochem Biophys Rep 2017; 10:287-296. [PMID: 29114576 PMCID: PMC5627143 DOI: 10.1016/j.bbrep.2017.04.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 03/09/2017] [Accepted: 04/22/2017] [Indexed: 11/18/2022] Open
Abstract
An aqueous electrohydrodynamic (EHD) floating liquid bridge is a unique environment for studying the influence of protonic currents (mA cm-2) in strong DC electric fields (kV cm-1) on the behavior of microorganisms. It forms in between two beakers filled with water when high-voltage is applied to these beakers. We recently discovered that exposure to this bridge has a stimulating effect on Escherichia coli.. In this work we show that the survival is due to a natural Faraday cage effect of the cell wall of these microorganisms using a simple 2D model. We further confirm this hypothesis by measuring and simulating the behavior of Bacillus subtilis subtilis, Neochloris oleoabundans, Saccharomyces cerevisiae and THP-1 monocytes. Their behavior matches the predictions of the model: cells without a natural Faraday cage like algae and monocytes are mostly killed and weakened, whereas yeast and Bacillus subtilis subtilis survive. The effect of the natural Faraday cage is twofold: First, it diverts the current from passing through the cell (and thereby killing it); secondly, because it is protonic it maintains the osmotic pressure in the cell wall, thereby mitigating cytolysis which would normally occur due to the low osmotic pressure of the surrounding medium. The method presented provides the basis for selective disinfection of solutions containing different microorganisms.
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Affiliation(s)
- Astrid H. Paulitsch-Fuchs
- Wetsus, European Centre of Excellence for Sustainable Water Technology,
Leeuwarden, The Netherlands
- Institute of Hygiene, Microbiology and Environmental Medicine, Medical
University of Graz, Graz, Austria
| | - Andrea Zsohár
- Wetsus, European Centre of Excellence for Sustainable Water Technology,
Leeuwarden, The Netherlands
| | - Adam D. Wexler
- Wetsus, European Centre of Excellence for Sustainable Water Technology,
Leeuwarden, The Netherlands
| | - Andrea Zauner
- Institute of Hygiene, Microbiology and Environmental Medicine, Medical
University of Graz, Graz, Austria
| | - Clemens Kittinger
- Institute of Hygiene, Microbiology and Environmental Medicine, Medical
University of Graz, Graz, Austria
| | - Joeri de Valença
- Wetsus, European Centre of Excellence for Sustainable Water Technology,
Leeuwarden, The Netherlands
| | - Elmar C. Fuchs
- Wetsus, European Centre of Excellence for Sustainable Water Technology,
Leeuwarden, The Netherlands
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Levin M, Pezzulo G, Finkelstein JM. Endogenous Bioelectric Signaling Networks: Exploiting Voltage Gradients for Control of Growth and Form. Annu Rev Biomed Eng 2017; 19:353-387. [PMID: 28633567 PMCID: PMC10478168 DOI: 10.1146/annurev-bioeng-071114-040647] [Citation(s) in RCA: 142] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Living systems exhibit remarkable abilities to self-assemble, regenerate, and remodel complex shapes. How cellular networks construct and repair specific anatomical outcomes is an open question at the heart of the next-generation science of bioengineering. Developmental bioelectricity is an exciting emerging discipline that exploits endogenous bioelectric signaling among many cell types to regulate pattern formation. We provide a brief overview of this field, review recent data in which bioelectricity is used to control patterning in a range of model systems, and describe the molecular tools being used to probe the role of bioelectrics in the dynamic control of complex anatomy. We suggest that quantitative strategies recently developed to infer semantic content and information processing from ionic activity in the brain might provide important clues to cracking the bioelectric code. Gaining control of the mechanisms by which large-scale shape is regulated in vivo will drive transformative advances in bioengineering, regenerative medicine, and synthetic morphology, and could be used to therapeutically address birth defects, traumatic injury, and cancer.
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Affiliation(s)
- Michael Levin
- Biology Department, Tufts University, Medford, Massachusetts 02155-4243;
- Allen Discovery Center, Tufts University, Medford, Massachusetts 02155;
| | - Giovanni Pezzulo
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome 00185, Italy;
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Pokorný J, Pokorný J, Borodavka F. Warburg effect-damping of electromagnetic oscillations. Electromagn Biol Med 2017; 36:270-278. [PMID: 28574758 DOI: 10.1080/15368378.2017.1326933] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mitochondrial dysfunction is a central defect in cells creating the Warburg and reverse Warburg effect cancers. However, the link between mitochondrial dysfunction and cancer has not yet been clearly explained. Decrease of mitochondrial oxidative energy production to about 50 % in comparison with healthy cells may be caused by inhibition of pyruvate transfer into mitochondrial matrix and/or disturbed H+ ion transfer across inner mitochondrial membrane into cytosol. Lowering of the inner membrane potential and shifting of the working point of mitochondria to high values of pH above an intermediate point causes reorganization of the ordered water layer at the mitochondrial membrane. The reorganized ordered water layers at high pH values release electrons which are transferred to the cytosol rim of the layer. The electrons damp electromagnetic activity of Warburg effect cancer cells or fibroblasts associated with reverse Warburg effect cancer cells leading to lowered electromagnetic activity, disturbed coherence, increased frequency of oscillations and decreased level of biological functions. In reverse Warburg effect cancers, associated fibroblasts supply energy-rich metabolites to the cancer cell resulting in increased power of electromagnetic field, fluctuations due to shift of oscillations to an unstable nonlinear region, decreased frequency and loss of coherence.
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Affiliation(s)
- Jiří Pokorný
- a Institute of Physics, Czech Academy of Sciences , Prague , Czech Republic
| | - Jan Pokorný
- a Institute of Physics, Czech Academy of Sciences , Prague , Czech Republic
| | - Fedir Borodavka
- a Institute of Physics, Czech Academy of Sciences , Prague , Czech Republic
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Multiferroic coreshell magnetoelectric nanoparticles as NMR sensitive nanoprobes for cancer cell detection. Sci Rep 2017; 7:1610. [PMID: 28487517 PMCID: PMC5431629 DOI: 10.1038/s41598-017-01647-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 03/31/2017] [Indexed: 02/07/2023] Open
Abstract
Magnetoelectric (ME) nanoparticles (MENs) intrinsically couple magnetic and electric fields. Using them as nuclear magnetic resonance (NMR) sensitive nanoprobes adds another dimension for NMR detection of biological cells based on the cell type and corresponding particle association with the cell. Based on ME property, for the first time we show that MENs can distinguish different cancer cells among themselves as well as from their normal counterparts. The core-shell nanoparticles are 30 nm in size and were not superparamagnetic. Due to presence of the ME effect, these nanoparticles can significantly enhance the electric field configuration on the cell membrane which serves as a signature characteristic depending on the cancer cell type and progression stage. This was clearly observed by a significant change in the NMR absorption spectra of cells incubated with MENs. In contrast, conventional cobalt ferrite magnetic nanoparticles (MNPs) did not show any change in the NMR absorption spectra. We conclude that different membrane properties of cells which result in distinct MEN organization and the minimization of electrical energy due to particle binding to the cells contribute to the NMR signal. The nanoprobe based NMR spectroscopy has the potential to enable rapid screening of cancers and impact next-generation cancer diagnostic exams.
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Tuszynski JA, Wenger C, Friesen DE, Preto J. An Overview of Sub-Cellular Mechanisms Involved in the Action of TTFields. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2016; 13:E1128. [PMID: 27845746 PMCID: PMC5129338 DOI: 10.3390/ijerph13111128] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Revised: 10/23/2016] [Accepted: 11/07/2016] [Indexed: 12/13/2022]
Abstract
Long-standing research on electric and electromagnetic field interactions with biological cells and their subcellular structures has mainly focused on the low- and high-frequency regimes. Biological effects at intermediate frequencies between 100 and 300 kHz have been recently discovered and applied to cancer cells as a therapeutic modality called Tumor Treating Fields (TTFields). TTFields are clinically applied to disrupt cell division, primarily for the treatment of glioblastoma multiforme (GBM). In this review, we provide an assessment of possible physical interactions between 100 kHz range alternating electric fields and biological cells in general and their nano-scale subcellular structures in particular. This is intended to mechanistically elucidate the observed strong disruptive effects in cancer cells. Computational models of isolated cells subject to TTFields predict that for intermediate frequencies the intracellular electric field strength significantly increases and that peak dielectrophoretic forces develop in dividing cells. These findings are in agreement with in vitro observations of TTFields' disruptive effects on cellular function. We conclude that the most likely candidates to provide a quantitative explanation of these effects are ionic condensation waves around microtubules as well as dielectrophoretic effects on the dipole moments of microtubules. A less likely possibility is the involvement of actin filaments or ion channels.
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Affiliation(s)
- Jack A Tuszynski
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada.
- Department of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada.
| | - Cornelia Wenger
- The Institute of Biophysics and Biomedical Engineering, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal.
| | - Douglas E Friesen
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada.
| | - Jordane Preto
- Department of Oncology, University of Alberta, Edmonton, AB T6G 1Z2, Canada.
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32
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Abstract
A sufficiently complex set of molecules, if subject to perturbation, will self-organize and show emergent behaviour. If such a system can take on information it will become subject to natural selection. This could explain how self-replicating molecules evolved into life and how intelligence arose. A pivotal step in this evolutionary process was of course the emergence of the eukaryote and the advent of the mitochondrion, which both enhanced energy production per cell and increased the ability to process, store and utilize information. Recent research suggest that from its inception life embraced quantum effects such as 'tunnelling' and 'coherence' while competition and stressful conditions provided a constant driver for natural selection. We believe that the biphasic adaptive response to stress described by hormesis-a process that captures information to enable adaptability, is central to this whole process. Critically, hormesis could improve mitochondrial quantum efficiency, improving the ATP/ROS ratio, whereas inflammation, which is tightly associated with the aging process, might do the opposite. This all suggests that to achieve optimal health and healthy aging, one has to sufficiently stress the system to ensure peak mitochondrial function, which itself could reflect selection of optimum efficiency at the quantum level.
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Affiliation(s)
- Alistair V W Nunn
- Research Centre for Optimal Health, Department of Life Sciences, University of Westminster, London W1W 6UW, U.K.
| | - Geoffrey W Guy
- GW Pharmaceuticals, Porton Down, Salisbury, Wiltshire SP4 0JQ, U.K
| | - Jimmy D Bell
- Research Centre for Optimal Health, Department of Life Sciences, University of Westminster, London W1W 6UW, U.K
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33
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Wexler AD, Drusová S, Woisetschläger J, Fuchs EC. Non-equilibrium thermodynamics and collective vibrational modes of liquid water in an inhomogeneous electric field. Phys Chem Chem Phys 2016; 18:16281-92. [PMID: 27253197 DOI: 10.1039/c5cp07218b] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this experiment liquid water is subject to an inhomogeneous electric field (∇(2)Ea≈ 10(10) V m(2)) using a high voltage (20 kV) point-plane electrode system. Using interferometry it was found that the application of a strong electric field gradient to water generates local changes in the refractive index of the liquid, polarizes the surface and creates a downward moving electro-convective jet. A maximum temperature difference of 1 °C is measured in the immediate vicinity of the point electrode. Raman spectroscopy performed on water reveals an enhancement of the vibrational collective modes (3250 cm(-1)) as well as an increase in the local mode (3490 cm(-1)) energy. This bimodal enhancement indicates that the spectral changes are not due to temperature changes. The intense field gradient thus establishes an excited subpopulation of vibrational oscillators far from thermal equilibrium. Delocalization of the collective vibrational mode spatially expands this excited population beyond the microscale. Hindered rotational freedom due to electric field pinning of molecular dipoles retards the heat flow and generates a chemical potential gradient. These changes are responsible for the observed changes in the refractive index and temperature. It is demonstrated that polar liquids can thus support local non-equilibrium thermodynamic transient states critical to biochemical and environmental processes.
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Affiliation(s)
- Adam D Wexler
- Applied Water Physics, Wetsus European Center of Excellence for Sustainable Water Technology, 8911MA Leeuwarden, Netherlands.
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34
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Scholkmann F. Long range physical cell-to-cell signalling via mitochondria inside membrane nanotubes: a hypothesis. Theor Biol Med Model 2016; 13:16. [PMID: 27267202 PMCID: PMC4896004 DOI: 10.1186/s12976-016-0042-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 05/27/2016] [Indexed: 02/07/2023] Open
Abstract
Coordinated interaction of single cells by cell-to-cell communication (signalling) enables complex behaviour necessary for the functioning of multicellular organisms. A quite newly discovered cell-to-cell signalling mechanism relies on nanotubular cell-co-cell connections, termed "membrane nanotubes" (MNTs). The present paper presents the hypothesis that mitochondria inside MNTs can form a connected structure (mitochondrial network) which enables the exchange of energy and signals between cells. It is proposed that two modes of energy and signal transmission may occur: electrical/electrochemical and electromagnetic (optical). Experimental work supporting the hypothesis is reviewed, and suggestions for future research regarding the discussed topic are given.
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Affiliation(s)
- Felix Scholkmann
- Biomedical Optics Research Laboratory, Department of Neonatology, University Hospital Zurich, University of Zurich, Frauenklinikstr. 10, 8091, Zurich, Switzerland.
- Research Office for Complex Physical and Biological Systems (ROCoS), Mutschellenstr. 179, 8038, Zurich, Switzerland.
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35
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Cantero MDR, Perez PL, Smoler M, Villa Etchegoyen C, Cantiello HF. Electrical Oscillations in Two-Dimensional Microtubular Structures. Sci Rep 2016; 6:27143. [PMID: 27256791 PMCID: PMC4891677 DOI: 10.1038/srep27143] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 05/11/2016] [Indexed: 12/27/2022] Open
Abstract
Microtubules (MTs) are unique components of the cytoskeleton formed by hollow cylindrical structures of αβ tubulin dimeric units. The structural wall of the MT is interspersed by nanopores formed by the lateral arrangement of its subunits. MTs are also highly charged polar polyelectrolytes, capable of amplifying electrical signals. The actual nature of these electrodynamic capabilities remains largely unknown. Herein we applied the patch clamp technique to two-dimensional MT sheets, to characterize their electrical properties. Voltage-clamped MT sheets generated cation-selective oscillatory electrical currents whose magnitude depended on both the holding potential, and ionic strength and composition. The oscillations progressed through various modes including single and double periodic regimes and more complex behaviours, being prominent a fundamental frequency at 29 Hz. In physiological K(+) (140 mM), oscillations represented in average a 640% change in conductance that was also affected by the prevalent anion. Current injection induced voltage oscillations, thus showing excitability akin with action potentials. The electrical oscillations were entirely blocked by taxol, with pseudo Michaelis-Menten kinetics and a KD of ~1.29 μM. The findings suggest a functional role of the nanopores in the MT wall on the genesis of electrical oscillations that offer new insights into the nonlinear behaviour of the cytoskeleton.
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Affiliation(s)
- María del Rocío Cantero
- Cátedra de Biofísica, Facultad de Odontología. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Paula L. Perez
- Cátedra de Biofísica, Facultad de Odontología. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mariano Smoler
- Cátedra de Biofísica, Facultad de Odontología. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Cecilia Villa Etchegoyen
- Cátedra de Biofísica, Facultad de Odontología. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Horacio F. Cantiello
- Cátedra de Biofísica, Facultad de Odontología. Universidad de Buenos Aires, Buenos Aires, Argentina
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36
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Jandová A, Pokorný J, Pokorný J, Kobilková J, Nedbalová M, Čoček A, Jelínek F, Vrba J, Vrba J, Dohnalová A, Kytnarová J, Tuszyński JA, Foletti A. Diseases caused by defects of energy level and loss of coherence in living cells. Electromagn Biol Med 2016; 34:151-5. [PMID: 26098528 DOI: 10.3109/15368378.2015.1036076] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Human and animal diseases are brought about by pathological alterations of production, composition, and conformation of macromolecules and structures in cells. Additional contributing factors include changes in physiological states caused by disturbances of energy supply, energy transduction, energy dissipation in moving or oscillating parts, and parasitic energy consumption. Disturbances of energy states may endanger existence of the system. The cell-mediated immunity (CMI) response of T lymphocytes correlating with their adherence properties was examined using antigen prepared from the serum of inbred laboratory mice strain C3H H(2k) infected with lactate dehydrogenase elevating (LDH) virus. LDH virus is a parasite on the cellular energy system. Significant CMI response was elicited in T lymphocytes prepared from the blood of patients with cancer of different phenotypes, acute myocardial infarctions, schizophrenia, and recurrent spontaneous abortions in early pregnancy from unknown reasons. The CMI response is assumed to monitor transferred information about decreased levels of energy states and decoherence in the cells caused by mitochondrial malfunction, parasitic consumption, production of lactate, and possibly other disturbances. The LDH virus infection or similar pathological processes caused by different agents might be connected with the diseases and monitored by the examined CMI response. A large amount of mitoses with chromosome defects in aborted fetuses suggest increased mutability of genomes caused by defective energy states.
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Affiliation(s)
- Anna Jandová
- Department of Obstetrics and Gynaecology, 1st Faculty of Medicine, Charles University , Prague , Czech Republic
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37
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Yin Y, Niu L, Zhu X, Zhao M, Zhang Z, Mann S, Liang D. Non-equilibrium behaviour in coacervate-based protocells under electric-field-induced excitation. Nat Commun 2016; 7:10658. [PMID: 26876162 PMCID: PMC4756681 DOI: 10.1038/ncomms10658] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 01/11/2016] [Indexed: 12/17/2022] Open
Abstract
Although numerous strategies are now available to generate rudimentary forms of synthetic cell-like entities, minimal progress has been made in the sustained excitation of artificial protocells under non-equilibrium conditions. Here we demonstrate that the electric field energization of coacervate microdroplets comprising polylysine and short single strands of DNA generates membrane-free protocells with complex, dynamical behaviours. By confining the droplets within a microfluidic channel and applying a range of electric field strengths, we produce protocells that exhibit repetitive cycles of vacuolarization, dynamical fluctuations in size and shape, chaotic growth and fusion, spontaneous ejection and sequestration of matter, directional capture of solute molecules, and pulsed enhancement of enzyme cascade reactions. Our results highlight new opportunities for the study of non-equilibrium phenomena in synthetic protocells, provide a strategy for inducing complex behaviour in electrostatically assembled soft matter microsystems and illustrate how dynamical properties can be activated and sustained in microcompartmentalized media.
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Affiliation(s)
- Yudan Yin
- Beijing National Laboratory for Molecular Sciences, MOE Key Laboratory of Polymer Chemistry and Physics, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Lin Niu
- Beijing National Laboratory for Molecular Sciences, MOE Key Laboratory of Polymer Chemistry and Physics, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Xiaocui Zhu
- Beijing National Laboratory for Molecular Sciences, MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Meiping Zhao
- Beijing National Laboratory for Molecular Sciences, MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Zexin Zhang
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou 215006, China
| | - Stephen Mann
- Centre for Protolife Research, School of Chemistry, University of Bristol, Bristol BS8 1TS, UK
| | - Dehai Liang
- Beijing National Laboratory for Molecular Sciences, MOE Key Laboratory of Polymer Chemistry and Physics, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
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38
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Chen G, Roy I, Yang C, Prasad PN. Nanochemistry and Nanomedicine for Nanoparticle-based Diagnostics and Therapy. Chem Rev 2016; 116:2826-85. [DOI: 10.1021/acs.chemrev.5b00148] [Citation(s) in RCA: 1014] [Impact Index Per Article: 126.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Guanying Chen
- Institute
for Lasers, Photonics, and Biophotonics and Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
- School
of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China
| | - Indrajit Roy
- Institute
for Lasers, Photonics, and Biophotonics and Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
- Department
of Chemistry, University of Delhi, Delhi 110007, India
| | - Chunhui Yang
- School
of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China
| | - Paras N. Prasad
- Institute
for Lasers, Photonics, and Biophotonics and Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260, United States
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39
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Lugli F, Toschi F, Biscarini F, Zerbetto F. Electric Field Effects on Short Fibrils of Aβ Amyloid Peptides. J Chem Theory Comput 2015; 6:3516-26. [PMID: 26617101 DOI: 10.1021/ct1001335] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amyloid fibrils are highly ordered protein aggregates, which are associated with many neurodegenerative diseases. The assembling dynamics of monomeric beta-amyloid peptides, Aβ, into small aggregates (and then into long fibrils) is still debated and has become a hot topic. In this study, we conducted molecular dynamics simulations in explicit water of small Aβ protofibrils (from monomer to pentamer) under the perturbation of an externally applied electric field with the aim of investigating the fundamental molecular interactions involved in the aggregation mechanism. Dynamics of small adducts of Aβ(16-42) in the presence of an electric field, which was shown before to accelerate the conformational change of a single molecule, indicate that the structural resilience increases with the number of molecules in the aggregate. In particular, for 50 ns, the pentamer shows an enhanced stability in secondary structure, number of hydrogen bonds, and number of salt bridges, even in the presence of the field perturbation. The resilience to the field perturbation is linked to the variation of the induced dipole moment of the aggregates that tends to level off very rapidly with the growing number of molecules, thereby reducing the energy available per molecule to produce structural changes. The results also show that in the presence of the field the stability of the hydrophobic second β-sheet (β2, residues 31-42) is higher than that of the first one (β1, residues 18-26). In particular, we identify Gly33, Gly37, and Met35 as the most important residues that stabilize the intermolecular packing and may act as nucleation sites for fibrillization. Furthermore, dynamics of the full-length Aβ(1-42) pentameric aggregate, which include the highly charged random coil residues 1-15, confirmed the key role of the second hydrophobic core in the protofibril structure.
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Affiliation(s)
- Francesca Lugli
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy and ISMN CNR, V. Gobetti, Bologna, Italy
| | - Francesca Toschi
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy and ISMN CNR, V. Gobetti, Bologna, Italy
| | - Fabio Biscarini
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy and ISMN CNR, V. Gobetti, Bologna, Italy
| | - Francesco Zerbetto
- Dipartimento di Chimica "G. Ciamician", Università di Bologna, via F. Selmi 2, 40126 Bologna, Italy and ISMN CNR, V. Gobetti, Bologna, Italy
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40
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Mitochondrial emitted electromagnetic signals mediate retrograde signaling. Med Hypotheses 2015; 85:810-8. [DOI: 10.1016/j.mehy.2015.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Revised: 09/25/2015] [Accepted: 10/09/2015] [Indexed: 12/19/2022]
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41
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Shi Y, Acerson MJ, Shuford KL, Shaw BF. Voltage-Induced Misfolding of Zinc-Replete ALS Mutant Superoxide Dismutase-1. ACS Chem Neurosci 2015. [PMID: 26207449 DOI: 10.1021/acschemneuro.5b00146] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The monomerization of Cu, Zn superoxide dismutase (SOD1) is an early step along pathways of misfolding linked to amyotrophic lateral sclerosis (ALS). Monomerization requires the reversal of two post-translational modifications that are thermodynamically favorable: (i) dissociation of active-site metal ions and (ii) reduction of intramolecular disulfide bonds. This study found, using amide hydrogen/deuterium (H/D) exchange, capillary electrophoresis, and lysine-acetyl protein charge ladders, that ALS-linked A4V SOD1 rapidly monomerizes and partially unfolds in an external electric field (of physiological strength), without loss of metal ions, exposure to disulfide-reducing agents, or Joule heating. Voltage-induced monomerization was not observed for metal-free A4V SOD1, metal-free WT SOD1, or metal-loaded WT SOD1. Computational modeling suggested a mechanism for this counterintuitive effect: subunit macrodipoles of dimeric SOD1 are antiparallel and amplified 2-fold by metal coordination, which increases torque at the dimer interface as subunits rotate to align with the electric field.
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Affiliation(s)
- Yunhua Shi
- Department
of Chemistry and
Biochemistry, Baylor University, Waco, Texas 76706, United States
| | - Mark J. Acerson
- Department
of Chemistry and
Biochemistry, Baylor University, Waco, Texas 76706, United States
| | - Kevin L. Shuford
- Department
of Chemistry and
Biochemistry, Baylor University, Waco, Texas 76706, United States
| | - Bryan F. Shaw
- Department
of Chemistry and
Biochemistry, Baylor University, Waco, Texas 76706, United States
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42
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Pokorný J, Pokorný J, Foletti A, Kobilková J, Vrba J, Vrba J. Mitochondrial Dysfunction and Disturbed Coherence: Gate to Cancer. Pharmaceuticals (Basel) 2015; 8:675-95. [PMID: 26437417 PMCID: PMC4695805 DOI: 10.3390/ph8040675] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 09/06/2015] [Accepted: 09/11/2015] [Indexed: 12/21/2022] Open
Abstract
Continuous energy supply, a necessary condition for life, excites a state far from thermodynamic equilibrium, in particular coherent electric polar vibrations depending on water ordering in the cell. Disturbances in oxidative metabolism and coherence are a central issue in cancer development. Oxidative metabolism may be impaired by decreased pyruvate transfer to the mitochondrial matrix, either by parasitic consumption and/or mitochondrial dysfunction. This can in turn lead to disturbance in water molecules’ ordering, diminished power, and coherence of the electromagnetic field. In tumors with the Warburg (reverse Warburg) effect, mitochondrial dysfunction affects cancer cells (fibroblasts associated with cancer cells), and the electromagnetic field generated by microtubules in cancer cells has low power (high power due to transport of energy-rich metabolites from fibroblasts), disturbed coherence, and a shifted frequency spectrum according to changed power. Therapeutic strategies restoring mitochondrial function may trigger apoptosis in treated cells; yet, before this step is performed, induction (inhibition) of pyruvate dehydrogenase kinases (phosphatases) may restore the cancer state. In tumor tissues with the reverse Warburg effect, Caveolin-1 levels should be restored and the transport of energy-rich metabolites interrupted to cancer cells. In both cancer phenotypes, achieving permanently reversed mitochondrial dysfunction with metabolic-modulating drugs may be an effective, specific anti-cancer strategy.
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Affiliation(s)
- Jiří Pokorný
- Institute of Photonics and Electronics, Czech Academy of Sciences, Chaberská 57, 182 51 Prague 8, Czech Republic.
| | - Jan Pokorný
- Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague 8, Czech Republic.
| | - Alberto Foletti
- Institute of Translational Pharmacology, National Research Council-CNR, Via Fosso del Cavaliere 100, Rome 00133, Italy.
- Clinical Biophysics International Research Group, via Maggio 21, Lugano 6900, Switzerland.
| | - Jitka Kobilková
- Department of Obstetrics and Gynaecology, 1st Faculty of Medicine, Charles University in Prague, Apolinářská 18, 128 00 Prague 2, Czech Republic.
| | - Jan Vrba
- Faculty of Electrical Engineering, Czech Technical University in Prague, Technická 2, 166 27 Prague 6, Czech Republic.
| | - Jan Vrba
- Faculty of Biomedical Engineering, Czech Technical University in Kladno, Sitná Square 3105, 272 01 Kladno, Czech Republic.
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43
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Hamblin MR, Chiang LY, Lakshmanan S, Huang YY, Garcia-Diaz M, Karimi M, de Souza Rastelli AN, Chandran R. Nanotechnology for photodynamic therapy: a perspective from the Laboratory of Dr. Michael R. Hamblin in the Wellman Center for Photomedicine at Massachusetts General Hospital and Harvard Medical School. NANOTECHNOLOGY REVIEWS 2015; 4:359-372. [PMID: 26640747 PMCID: PMC4666539 DOI: 10.1515/ntrev-2015-0027] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The research interests of the Hamblin Laboratory are broadly centered on the use of different kinds of light to treat many different diseases. Photodynamic therapy (PDT) uses the combination of dyes with visible light to produce reactive oxygen species and kill bacteria, cancer cells and destroy unwanted tissue. Likewise, UV light is also good at killing especially pathogens. By contrast, red or near-infrared light can have the opposite effect, to act to preserve tissue from dying and can stimulate healing and regeneration. In all these applications, nanotechnology is having an ever-growing impact. In PDT, self-assembled nano-drug carriers (micelles, liposomes, etc.) play a great role in solubilizing the photosensitizers, metal nanoparticles can carry out plasmon resonance enhancement, and fullerenes can act as photosensitizers, themselves. In the realm of healing, single-walled carbon nanotubes can be electrofocused to produce nano-electonic biomedical devices, and nanomaterials will play a great role in restorative dentistry.
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Affiliation(s)
| | - Long Y. Chiang
- Department of Chemistry, University of Massachusetts, Lowell, MA, USA
| | - Shanmugamurthy Lakshmanan
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom Street, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, Boston, MA, USA
| | - Ying-Ying Huang
- Wellman Center for Photomedicine, Massachusetts General Hospital, 40 Blossom Street, Boston, MA 02114, USA; Department of Dermatology, Harvard Medical School, Boston, MA, USA
| | | | - Mahdi Karimi
- Iran University of Medical Science, Tehran, Iran
| | | | - Rakkiyappan Chandran
- Joint School of Nanoscience and Nanoengineering, University of North Carolina, Greensboro, NC, USA
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44
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Levin M. Molecular bioelectricity: how endogenous voltage potentials control cell behavior and instruct pattern regulation in vivo. Mol Biol Cell 2015; 25:3835-50. [PMID: 25425556 PMCID: PMC4244194 DOI: 10.1091/mbc.e13-12-0708] [Citation(s) in RCA: 221] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
In addition to biochemical gradients and transcriptional networks, cell behavior is regulated by endogenous bioelectrical cues originating in the activity of ion channels and pumps, operating in a wide variety of cell types. Instructive signals mediated by changes in resting potential control proliferation, differentiation, cell shape, and apoptosis of stem, progenitor, and somatic cells. Of importance, however, cells are regulated not only by their own Vmem but also by the Vmem of their neighbors, forming networks via electrical synapses known as gap junctions. Spatiotemporal changes in Vmem distribution among nonneural somatic tissues regulate pattern formation and serve as signals that trigger limb regeneration, induce eye formation, set polarity of whole-body anatomical axes, and orchestrate craniofacial patterning. New tools for tracking and functionally altering Vmem gradients in vivo have identified novel roles for bioelectrical signaling and revealed the molecular pathways by which Vmem changes are transduced into cascades of downstream gene expression. Because channels and gap junctions are gated posttranslationally, bioelectrical networks have their own characteristic dynamics that do not reduce to molecular profiling of channel expression (although they couple functionally to transcriptional networks). The recent data provide an exciting opportunity to crack the bioelectric code, and learn to program cellular activity at the level of organs, not only cell types. The understanding of how patterning information is encoded in bioelectrical networks, which may require concepts from computational neuroscience, will have transformative implications for embryogenesis, regeneration, cancer, and synthetic bioengineering.
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Affiliation(s)
- Michael Levin
- Biology Department, Center for Regenerative and Developmental Biology, Tufts University, Medford, MA 02155-4243
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45
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Cremer T, Cremer M, Hübner B, Strickfaden H, Smeets D, Popken J, Sterr M, Markaki Y, Rippe K, Cremer C. The 4D nucleome: Evidence for a dynamic nuclear landscape based on co-aligned active and inactive nuclear compartments. FEBS Lett 2015; 589:2931-43. [PMID: 26028501 DOI: 10.1016/j.febslet.2015.05.037] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 05/19/2015] [Accepted: 05/20/2015] [Indexed: 02/04/2023]
Abstract
Recent methodological advancements in microscopy and DNA sequencing-based methods provide unprecedented new insights into the spatio-temporal relationships between chromatin and nuclear machineries. We discuss a model of the underlying functional nuclear organization derived mostly from electron and super-resolved fluorescence microscopy studies. It is based on two spatially co-aligned, active and inactive nuclear compartments (ANC and INC). The INC comprises the compact, transcriptionally inactive core of chromatin domain clusters (CDCs). The ANC is formed by the transcriptionally active periphery of CDCs, called the perichromatin region (PR), and the interchromatin compartment (IC). The IC is connected to nuclear pores and serves nuclear import and export functions. The ANC is the major site of RNA synthesis. It is highly enriched in epigenetic marks for transcriptionally competent chromatin and RNA Polymerase II. Marks for silent chromatin are enriched in the INC. Multi-scale cross-correlation spectroscopy suggests that nuclear architecture resembles a random obstacle network for diffusing proteins. An increased dwell time of proteins and protein complexes within the ANC may help to limit genome scanning by factors or factor complexes to DNA exposed within the ANC.
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Affiliation(s)
- Thomas Cremer
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany.
| | - Marion Cremer
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Barbara Hübner
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Hilmar Strickfaden
- University of Alberta, Cross Cancer Institute Dept. of Oncology, Edmonton, AB, Canada
| | - Daniel Smeets
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Jens Popken
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Michael Sterr
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Yolanda Markaki
- Biocenter, Department Biology II, Ludwig Maximilians University (LMU), Martinsried, Germany
| | - Karsten Rippe
- German Cancer Research Center (DKFZ) & BioQuant Center, Research Group Genome Organization & Function, Heidelberg, Germany.
| | - Christoph Cremer
- Institute of Molecular Biology (IMB), Mainz and Institute of Pharmacy and Molecular Biotechnology (IPMB), University of Heidelberg, Germany.
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Pokorný J, Pokorný J, Kobilková J, Jandová A, Vrba J, Vrba J. Targeting mitochondria for cancer treatment - two types of mitochondrial dysfunction. Prague Med Rep 2015; 115:104-19. [PMID: 25626329 DOI: 10.14712/23362936.2014.41] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Two basic types of cancers were identified – those with the mitochondrial dysfunction in cancer cells (the Warburg effect) or in fibroblasts supplying energy rich metabolites to a cancer cell with functional mitochondria (the reverse Warburg effect). Inner membrane potential of the functional and dysfunctional mitochondria measured by fluorescent dyes (e.g. by Rhodamine 123) displays low and high values (apparent potential), respectively, which is in contrast to the level of oxidative metabolism. Mitochondrial dysfunction (full function) results in reduced (high) oxidative metabolism, low (high) real membrane potential, a simple layer (two layers) of transported protons around mitochondria, and high (low) damping of microtubule electric polar vibrations. Crucial modifications are caused by ordered water layer (exclusion zone). For the high oxidative metabolism one proton layer is at the mitochondrial membrane and the other at the outer rim of the ordered water layer. High and low damping of electric polar vibrations results in decreased and increased electromagnetic activity in cancer cells with the normal and the reverse Warburg effect, respectively. Due to nonlinear properties the electromagnetic frequency spectra of cancer cells and transformed fibroblasts are shifted in directions corresponding to their power deviations resulting in disturbances of interactions and escape from tissue control. The cancer cells and fibroblasts of the reverse Warburg effect tumors display frequency shifts in mutually opposite directions resulting in early generalization. High oxidative metabolism conditions high aggressiveness. Mitochondrial dysfunction, a gate to malignancy along the cancer transformation pathway, forms a narrow neck which could be convenient for cancer treatment.
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Affiliation(s)
- Jiří Pokorný
- Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jan Pokorný
- Institute of Physics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jitka Kobilková
- Department of Obstetrics and Gynaecology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, Czech Republic
| | - Anna Jandová
- Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Prague, Czech Republic
| | - Jan Vrba
- Faculty of Electrical Engineering, Czech Technical University in Prague, Prague, Czech Republic
| | - Jan Vrba
- Faculty of Biomedical Engineering, Czech Technical University in Prague, Kladno, Czech Republic
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Funk RHW. Endogenous electric fields as guiding cue for cell migration. Front Physiol 2015; 6:143. [PMID: 26029113 PMCID: PMC4429568 DOI: 10.3389/fphys.2015.00143] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 04/21/2015] [Indexed: 12/17/2022] Open
Abstract
This review covers two topics: (1) "membrane potential of low magnitude and related electric fields (bioelectricity)" and (2) "cell migration under the guiding cue of electric fields (EF)."Membrane potentials for this "bioelectricity" arise from the segregation of charges by special molecular machines (pumps, transporters, ion channels) situated within the plasma membrane of each cell type (including eukaryotic non-neural animal cells). The arising patterns of ion gradients direct many cell- and molecular biological processes such as embryogenesis, wound healing, regeneration. Furthermore, EF are important as guiding cues for cell migration and are often overriding chemical or topographic cues. In osteoblasts, for instance, the directional information of EF is captured by charged transporters on the cell membrane and transferred into signaling mechanisms that modulate the cytoskeleton and motor proteins. This results in a persistent directional migration along an EF guiding cue. As an outlook, we discuss questions concerning the fluctuation of EF and the frequencies and mapping of the "electric" interior of the cell. Another exciting topic for further research is the modeling of field concepts for such distant, non-chemical cellular interactions.
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Gerencsér L, Boros B, Derrien V, Hanson DK, Wraight CA, Sebban P, Maróti P. Stigmatellin probes the electrostatic potential in the QB site of the photosynthetic reaction center. Biophys J 2015; 108:379-94. [PMID: 25606686 DOI: 10.1016/j.bpj.2014.11.3463] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 11/13/2014] [Accepted: 11/19/2014] [Indexed: 11/25/2022] Open
Abstract
The electrostatic potential in the secondary quinone (QB) binding site of the reaction center (RC) of the photosynthetic bacterium Rhodobacter sphaeroides determines the rate and free energy change (driving force) of electron transfer to QB. It is controlled by the ionization states of residues in a strongly interacting cluster around the QB site. Reduction of the QB induces change of the ionization states of residues and binding of protons from the bulk. Stigmatellin, an inhibitor of the mitochondrial and photosynthetic respiratory chain, has been proven to be a unique voltage probe of the QB binding pocket. It binds to the QB site with high affinity, and the pK value of its phenolic group monitors the local electrostatic potential with high sensitivity. Investigations with different types of detergent as a model system of isolated RC revealed that the pK of stigmatellin was controlled overwhelmingly by electrostatic and slightly by hydrophobic interactions. Measurements showed a high pK value (>11) of stigmatellin in the QB pocket of the dark-state wild-type RC, indicating substantial negative potential. When the local electrostatics of the QB site was modulated by a single mutation, L213Asp → Ala, or double mutations, L213Asp-L212Glu → Ala-Ala (AA), the pK of stigmatellin dropped to 7.5 and 7.4, respectively, which corresponds to a >210 mV increase in the electrostatic potential relative to the wild-type RC. This significant pK drop (ΔpK > 3.5) decreased dramatically to (ΔpK > 0.75) in the RC of the compensatory mutant (AA+M44Asn → AA+M44Asp). Our results indicate that the L213Asp is the most important actor in the control of the electrostatic potential in the QB site of the dark-state wild-type RC, in good accordance with conclusions of former studies using theoretical calculations or light-induced charge recombination assay.
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Affiliation(s)
- László Gerencsér
- Department of Biophysics, University of Szeged, Szeged, Hungary; Department of Physics and Astronomy, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
| | - Bogáta Boros
- Department of Biophysics, University of Szeged, Szeged, Hungary
| | - Valerie Derrien
- Laboratoire de Chimie Physique, University of Paris-Sud, Orsay, France
| | - Deborah K Hanson
- Biosciences Divisions, Argonne National Laboratory, Argonne, Illinois
| | - Colin A Wraight
- Department of Biochemistry and Center for Biophysics and Computational Biology, University of Illinois, Urbana, Illinois
| | - Pierre Sebban
- Laboratoire de Chimie Physique, University of Paris-Sud, Orsay, France
| | - Péter Maróti
- Department of Biophysics, University of Szeged, Szeged, Hungary.
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Levin M. Endogenous bioelectrical networks store non-genetic patterning information during development and regeneration. J Physiol 2015; 592:2295-305. [PMID: 24882814 DOI: 10.1113/jphysiol.2014.271940] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Pattern formation, as occurs during embryogenesis or regeneration, is the crucial link between genotype and the functions upon which selection operates. Even cancer and aging can be seen as challenges to the continuous physiological processes that orchestrate individual cell activities toward the anatomical needs of an organism. Thus, the origin and maintenance of complex biological shape is a fundamental question for cell, developmental, and evolutionary biology, as well as for biomedicine. It has long been recognized that slow bioelectrical gradients can control cell behaviors and morphogenesis. Here, I review recent molecular data that implicate endogenous spatio-temporal patterns of resting potentials among non-excitable cells as instructive cues in embryogenesis, regeneration, and cancer. Functional data have implicated gradients of resting potential in processes such as limb regeneration, eye induction, craniofacial patterning, and head-tail polarity, as well as in metastatic transformation and tumorigenesis. The genome is tightly linked to bioelectric signaling, via ion channel proteins that shape the gradients, downstream genes whose transcription is regulated by voltage, and transduction machinery that converts changes in bioelectric state to second-messenger cascades. However, the data clearly indicate that bioelectric signaling is an autonomous layer of control not reducible to a biochemical or genetic account of cell state. The real-time dynamics of bioelectric communication among cells are not fully captured by transcriptomic or proteomic analyses, and the necessary-and-sufficient triggers for specific changes in growth and form can be physiological states, while the underlying gene loci are free to diverge. The next steps in this exciting new field include the development of novel conceptual tools for understanding the anatomical semantics encoded in non-neural bioelectrical networks, and of improved biophysical tools for reading and writing electrical state information into somatic tissues. Cracking the bioelectric code will have transformative implications for developmental biology, regenerative medicine, and synthetic bioengineering.
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Affiliation(s)
- Michael Levin
- Biology Department, Center for Regenerative and Developmental Biology, Tufts University, Medford, MA, USA
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Huston RL. Using the Electromagnetics of Cancer’s Centrosome Clusters to Attract Therapeutic Nanoparticles. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/abb.2015.63017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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