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Zhang X, Kang R, Liu Y, Yan Z, Xu Y, Yue T. From reversible to irreversible: When the membrane nanotube pearling is coupled with phase separation. Colloids Surf B Biointerfaces 2021; 209:112160. [PMID: 34736219 DOI: 10.1016/j.colsurfb.2021.112160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/17/2021] [Accepted: 10/07/2021] [Indexed: 12/11/2022]
Abstract
Membrane nanotubes, which are ubiquitous in biology and act as channels maintaining transport between different cells and organelles, readily undergo pearling in response to external stimuli. Membrane nanotube pearling involves generation of heterogeneous curvature coupled with redistribution of membrane components that may interfere with the shape recovery of pearled nanotubes. However, the mechanism underlying such delicate process remains unclear and difficult to study at the molecular scale in vivo. By means of molecular dynamics simulation, here we investigate pearling of multi-component membrane nanotubes and reversibility through manipulating system temperature and osmotic pressure. With the equilibrium shape of membrane nanotubes controlled by the osmotic pressure, our results demonstrate that the process of membrane nanotube pearling can be reversible or irreversible, depending on the phase segregation state. For the pearled nanotube releasing high surface energy, different lipid components redistribute along the tube axial direction. Lipids with unsaturated tails prefer gathering at the high-curvature shrinking region, whereas the swelling region is constituted by saturated lipids forming the liquid-ordered phase of a higher bending rigidity. Such curvature sensitive phase segregation minimizes the system free energy by reducing both the membrane bending energy and line tension at the phase boundary. As such, the pearled nanotube fails to recover its shape upon retracting stimuli, suggesting irreversibility of the membrane nanotube pearling coupled with phase separation. Given importance of membrane nanotube pearling in various cellular activities, these results provide a new mechanism of controlling equilibrium shapes of membrane nanotubes in complex cellular environment.
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Affiliation(s)
- Xiaoyang Zhang
- College of Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China
| | - Runshan Kang
- College of Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China
| | - Yingjie Liu
- Institute of Coastal Environmental Pollution Control, Key Laboratory of Marine Environment and Ecology, Ministry of Education, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China
| | - Zengshuai Yan
- National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China
| | - Yan Xu
- College of Electronic Engineering and Automation, Shandong University of Science and Technology, Qingdao 266590, China
| | - Tongtao Yue
- Institute of Coastal Environmental Pollution Control, Key Laboratory of Marine Environment and Ecology, Ministry of Education, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China.
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2
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Di Marino D, Bruno A, Grimaldi M, Scrima M, Stillitano I, Amodio G, Della Sala G, Romagnoli A, De Santis A, Moltedo O, Remondelli P, Boccia G, D'Errico G, D'Ursi AM, Limongelli V. Binding of the Anti-FIV Peptide C8 to Differently Charged Membrane Models: From First Docking to Membrane Tubulation. Front Chem 2020; 8:493. [PMID: 32676493 PMCID: PMC7333769 DOI: 10.3389/fchem.2020.00493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 05/13/2020] [Indexed: 12/11/2022] Open
Abstract
Gp36 is the virus envelope glycoproteins catalyzing the fusion of the feline immunodeficiency virus with the host cells. The peptide C8 is a tryptophan-rich peptide corresponding to the fragment 770W-I777 of gp36 exerting antiviral activity by binding the membrane cell and inhibiting the virus entry. Several factors, including the membrane surface charge, regulate the binding of C8 to the lipid membrane. Based on the evidence that imperceptible variation of membrane charge may induce a dramatic effect in several critical biological events, in the present work we investigate the effect induced by systematic variation of charge in phospholipid bilayers on the aptitude of C8 to interact with lipid membranes, the tendency of C8 to assume specific conformational states and the re-organization of the lipid bilayer upon the interaction with C8. Accordingly, employing a bottom-up multiscale protocol, including CD, NMR, ESR spectroscopy, atomistic molecular dynamics simulations, and confocal microscopy, we studied C8 in six membrane models composed of different ratios of zwitterionic/negatively charged phospholipids. Our data show that charge content modulates C8-membrane binding with significant effects on the peptide conformations. C8 in micelle solution or in SUV formed by DPC or DOPC zwitterionic phospholipids assumes regular β-turn structures that are progressively destabilized as the concentration of negatively charged SDS or DOPG phospholipids exceed 40%. Interaction of C8 with zwitterionic membrane surface is mediated by Trp1 and Trp4 that are deepened in the membrane, forming H-bonds and cation-π interactions with the DOPC polar heads. Additional stabilizing salt bridge interactions involve Glu2 and Asp3. MD and ESR data show that the C8-membrane affinity increases as the concentration of zwitterionic phospholipid increases. In the lipid membrane characterized by an excess of zwitterionic phospholipids, C8 is adsorbed at the membrane interface, inducing a stiffening of the outer region of the DOPC bilayer. However, the bound of C8 significantly perturbs the whole organization of lipid bilayer resulting in membrane remodeling. These events, measurable as a variation of the bilayer thickness, are the onset mechanism of the membrane fusion and vesicle tubulation observed in confocal microscopy by imaging zwitterionic MLVs in the presence of C8 peptide.
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Affiliation(s)
- Daniele Di Marino
- Department of Life and Environmental Sciences, New York-Marche Structural Biology Center (NY-MaSBiC), Polytechnic University of Marche, Ancona, Italy
| | - Agostino Bruno
- Department of Pharmacy, University of Naples "Federico II", Naples, Italy
| | | | - Mario Scrima
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | | | - Giuseppina Amodio
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy
| | - Grazia Della Sala
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Alice Romagnoli
- Department of Life and Environmental Sciences, New York-Marche Structural Biology Center (NY-MaSBiC), Polytechnic University of Marche, Ancona, Italy
| | - Augusta De Santis
- Department of Chemical Science, University of Naples Federico II, Naples, Italy
| | - Ornella Moltedo
- Department of Pharmacy, University of Salerno, Fisciano, Italy
| | - Paolo Remondelli
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy
| | - Giovanni Boccia
- Department of Medicine, Surgery and Dentistry "Scuola Medica Salernitana", University of Salerno, Baronissi, Italy
| | - Gerardino D'Errico
- Department of Chemical Science, University of Naples Federico II, Naples, Italy
| | | | - Vittorio Limongelli
- Department of Pharmacy, University of Naples "Federico II", Naples, Italy.,Faculty of Biomedical Sciences, Institute of Computational Science, Università della Svizzera italiana (USI), Lugano, Switzerland
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3
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Li S, Yan Z, Huang F, Zhang X, Yue T. How a lipid bilayer membrane responds to an oscillating nanoparticle: Promoted membrane undulation and directional wave propagation. Colloids Surf B Biointerfaces 2019; 187:110651. [PMID: 31784121 DOI: 10.1016/j.colsurfb.2019.110651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 11/15/2019] [Accepted: 11/16/2019] [Indexed: 01/14/2023]
Abstract
Mechanical forces acting on a plasma membrane are of essential importance to cellular functioning via inducing delicate change of the membrane shape with the underlying mechanism yet to be elucidated. Here, we introduce an oscillating nanoparticle (NP) interaction with a lipid bilayer membrane, using the coarse-grained simulation to investigate the dynamic membrane response to constrained mechanical stimulation, which is ubiquitous in biology. Our results demonstrate that, the membrane responds to an oscillating NP by generating nanoscale undulation waves, which immediately propagate through the membrane. In dynamics, propagation of the generated membrane undulation waves always starts from flattening of the region where the NP locates, thus producing a lateral force to propel the waves away from the point of stimulation. The speed of membrane undulation wave propagation is proportional to that of NP oscillation and accelerated by increasing the integral membrane surface tension, suggesting that both the membrane bending and stretching contribute to the energy driving the unique response of membrane undulation wave propagation.
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Affiliation(s)
- Shixin Li
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China
| | - Zengshuai Yan
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China
| | - Fang Huang
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China
| | - Xianren Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, China
| | - Tongtao Yue
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China.
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4
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Li S, Yan Z, Luo Z, Xu Y, Huang F, Zhang X, Yi X, Yue T. Mechanics of the Formation, Interaction, and Evolution of Membrane Tubular Structures. Biophys J 2019; 116:884-892. [PMID: 30795870 DOI: 10.1016/j.bpj.2019.01.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 01/07/2019] [Accepted: 01/29/2019] [Indexed: 01/27/2023] Open
Abstract
Membrane nanotubes, also known as membrane tethers, play important functional roles in many cellular processes, such as trafficking and signaling. Although considerable progresses have been made in understanding the physics regulating the mechanical behaviors of individual membrane nanotubes, relatively little is known about the formation of multiple membrane nanotubes due to the rapid occurring process involving strong cooperative effects and complex configurational transitions. By exerting a pair of external extraction upon two separate membrane regions, here, we combine molecular dynamics simulations and theoretical analysis to investigate how the membrane nanotube formation and pulling behaviors are regulated by the separation between the pulling forces and how the membrane protrusions interact with each other. As the force separation increases, different membrane configurations are observed, including an individual tubular protrusion, a relatively less deformed protrusion with two nanotubes on its top forming a V shape, a Y-shaped configuration through nanotube coalescence via a zipper-like mechanism, and two weakly interacting tubular protrusions. The energy profile as a function of the separation is determined. Moreover, the directional flow of lipid molecules accompanying the membrane shape transition is analyzed. Our results provide new, to our knowledge, insights at a molecular level into the interaction between membrane protrusions and help in understanding the formation and evolution of intra- and intercellular membrane tubular networks involved in numerous cell activities.
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Affiliation(s)
- Shixin Li
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, China
| | - Zengshuai Yan
- Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, China
| | - Zhen Luo
- Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, China
| | - Yan Xu
- Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, China
| | - Fang Huang
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, China
| | - Xianren Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, China
| | - Xin Yi
- Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, China; Beijing Innovation Center for Engineering Science and Advanced Technology, Peking University, Beijing, China.
| | - Tongtao Yue
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao, China; Center for Bioengineering and Biotechnology, College of Chemical Engineering, China University of Petroleum (East China), Qingdao, China.
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5
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Yan Z, Li S, Luo Z, Xu Y, Yue T. Membrane nanotube pearling restricted by confined polymers. SOFT MATTER 2018; 14:9383-9392. [PMID: 30418454 DOI: 10.1039/c8sm01711e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Increasing evidence showed that membrane nanotubes readily undergo pearling in response to external stimuli, while long tubular membrane structures have been observed connecting cells and functioning as channels for intercellular transport, raising a fundamental question of how the stability of membrane nanotubes is maintained in the cellular environment. Here, combining dissipative particle dynamics simulations, free energy calculations, and a force analysis, we propose and demonstrate that nanotube pearling can be restricted by confined polymers, which can be DNA and protein chains transported through the nanotubes, or actin filaments participating in tube formation and elongation. Thermodynamically, nanotube pearling releases the membrane surface energy, but costs bending energies of both the membrane and the confined polymers. Following the mechanism, the pearling of nanotubes confining longer and stiffer polymers is more difficult as it costs larger polymer bending energies. In dynamics, nanotube pearling occurs by repelling polymers from the region of nanotube shrinking to that of swelling. Shorter polymers can be readily repelled owing to the unbalanced force exerted by the shrinking tube region, whereas longer polymers tend to be trapped at the shrinking region to retard the nanotube pearling. Besides the low surface tension maintained by lipid reservoirs kept in living cells, our results supplement the explanation for the stability of membrane nanotubes, and open up a new avenue to manipulate the shape deformation of tubular membrane structures for study of many biological processes.
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Affiliation(s)
- Zengshuai Yan
- State Key Laboratory of Heavy Oil Processing, China University of Petroleum (East China), Qingdao 266580, China.
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Liu X, Tian F, Yue T, Zhang X, Zhong C. Exploring the shape deformation of biomembrane tubes with theoretical analysis and computer simulation. SOFT MATTER 2016; 12:9077-9085. [PMID: 27747359 DOI: 10.1039/c6sm01903j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The shape deformation of membrane nanotubes is studied by a combination of theoretical analysis and molecular simulation. First we perform free energy analysis to demonstrate the effects of various factors on two ideal states for the pearling transition, and then we carry out dissipative particle dynamics simulations, through which various types of membrane tube deformation are found, including membrane pearling, buckling, and bulging. Different models for inducing tube deformation, including the osmotic pressure, area difference and spontaneous curvature models, are considered to investigate tubular instabilities. Combined with free energy analysis, our simulations show that the origin of the deformation of membrane tubes in different models can be classified into two categories: effective spontaneous curvature and membrane tension. We further demonstrate that for different models, a positive membrane tension is required for the pearling transition. Finally we show that different models can be coupled to effectively deform the membrane tube.
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Affiliation(s)
- Xuejuan Liu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China.
| | - Falin Tian
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China.
| | - Tongtao Yue
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, P. R. China
| | - Xianren Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China.
| | - Chongli Zhong
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China. and Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing 100029, P. R. China
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7
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Arai N, Yoshimoto Y, Yasuoka K, Ebisuzaki T. Self-assembly behaviours of primitive and modern lipid membrane solutions: a coarse-grained molecular simulation study. Phys Chem Chem Phys 2016; 18:19426-32. [PMID: 27378100 DOI: 10.1039/c6cp02380k] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Researchers have studied the origin of life and the process of evolution on early Earth for decades. However, we lack a comprehensive understanding of biogenesis, because there are many stages in the formation and growth of the first cell. We investigate the self-replication processes of coacervate protocells using computer simulations of single-chain lipid and phospholipid aqueous mixtures. Based on a morphological phase diagram, we develop a model of prebiotic self-replication driven by only environmental factors (i.e. temperature and lipid concentrations) without any external force. Moreover, we investigate high concentration structures during the process of self-replication. These structures have an advantage in fusion and repair of cell membranes. Therefore, lipid hot spots may have existed in primordial soup.
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Affiliation(s)
- Noriyoshi Arai
- Department of Mechanical Engineering, Kindai University, Higashiosaka, Osaka, Japan.
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8
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Tian F, Yue T, Dong W, Zhang X. Membrane tube pearling induced by a coupling of osmotic pressure and nanoparticle adhesion. Mol Phys 2016. [DOI: 10.1080/00268976.2016.1161855] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Falin Tian
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, China
- Laboratoire de Chimie, Ecole Normale Superieure de Lyon, Lyon Cedex, France
| | - Tongtao Yue
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, China
| | - Wei Dong
- Laboratoire de Chimie, Ecole Normale Superieure de Lyon, Lyon Cedex, France
| | - Xianren Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, China
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Yue T, Tian F, Sun M, Zhang X, Huang F. Inter-tube adhesion mediates a new pearling mechanism. Phys Chem Chem Phys 2016; 18:361-74. [PMID: 26616465 DOI: 10.1039/c5cp04579g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A common mechanism for intracellular transport is the controlled shape transformation, also known as pearling, of membrane tubes. Exploring how tube pearling takes place is thus of quite importance to not only understand the bio-functions of tubes, but also promote their potential biomedical applications. While the pearling mechanism of one single tube is well understood, both the pathway and the mechanism of pearling of multiple tubes still remain unclear. Herein, by means of computer simulations we show that the tube pearling can be mediated by the inter-tube adhesion. By increasing the inter-tube adhesion strength, each tube undergoes a discontinuous transition from no pearling to thorough pearling. The discontinuous pearling transition is ascribed to the competitive variation between tube surface tension and the extent of inter-tube adhesion. Besides, the final pearling instability is also affected by tube diameter and inter-tube orientation. Thinner tubes undergo inter-tube lipid diffusion before completion of pearling. The early lipid diffusion reduces the extent of inter-tube adhesion and thus restrains the subsequent pearling. Therefore, only partial or no pearling can take place for two thinner tubes. For two perpendicular tubes, the pearling is also observed, but with different pathways and higher efficiency. The finite size effect is discussed by comparing the pearling of tubes with different lengths. It is expected that this work will not only provide new insights into the mechanism of membrane tube pearling, but also shed light on the potential applications in biomaterials science and nanomedicine.
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Affiliation(s)
- Tongtao Yue
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266580, China.
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Yue T, Xu Y, Sun M, Zhang X, Huang F. How tubular aggregates interact with biomembranes: wrapping, fusion and pearling. Phys Chem Chem Phys 2016; 18:1082-91. [DOI: 10.1039/c5cp06511a] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
How soft tubular aggregates interact with biomembranes is crucial for understanding the formation of membrane tubes connecting two eukaryotic cells, which are initially created from one cell and then connect with the other.
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Affiliation(s)
- Tongtao Yue
- State Key Laboratory of Heavy Oil Processing
- Center for Bioengineering and Biotechnology
- China University of Petroleum (East China)
- Qingdao
- China
| | - Yan Xu
- State Key Laboratory of Heavy Oil Processing
- Center for Bioengineering and Biotechnology
- China University of Petroleum (East China)
- Qingdao
- China
| | - Mingbin Sun
- State Key Laboratory of Heavy Oil Processing
- Center for Bioengineering and Biotechnology
- China University of Petroleum (East China)
- Qingdao
- China
| | - Xianren Zhang
- State Key Laboratory of Organic-Inorganic Composites
- Beijing University of Chemical Technology
- Beijing
- China
| | - Fang Huang
- State Key Laboratory of Heavy Oil Processing
- Center for Bioengineering and Biotechnology
- China University of Petroleum (East China)
- Qingdao
- China
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Yue T, Zhang X, Huang F. Molecular modeling of membrane responses to the adsorption of rotating nanoparticles: promoted cell uptake and mechanical membrane rupture. SOFT MATTER 2015; 11:456-465. [PMID: 25388826 DOI: 10.1039/c4sm01760a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Recently, a unique dynamic magnetic field was developed to induce the rotational movement of superparamagnetic iron oxide nanoparticles. This technique has been applied to remotely control both cellular internalization and apoptosis. Therefore, a thorough understanding of how a lipid membrane responds to the introduction of rotating NPs is quite important to promote the applications of this technique in a variety of biomedical area. Here, we performed Dissipative Particle Dynamics (DPD) simulations to systematically investigate the interaction mechanism between lipid membranes and rotating NPs. Two kinds of membrane responses are observed. One is the promoted cell uptake and the other is the mechanical membrane rupture. The promoting effect of NP rotation on the cell uptake is ascribed to the enhanced membrane monolayer protrusion, which can wrap the NP from the top side. Meanwhile, the rotating NP exerts a shearing force on the membrane. Accordingly, the membrane undergoes a local distortion around the NP. If the shearing force exceeds a critical value, the local membrane distortion develops into a mechanical rupture. A number of factors, like NP size, NP shape, ligand density and rotation speed, are critical in both of the above membrane responses.
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Affiliation(s)
- Tongtao Yue
- State Key Laboratory of Heavy Oil Processing, Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266580, China.
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