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Vo ATN, Murphy MA, Phan PK, Prabhu RK, Stone TW. Effect of Force Field Resolution on Membrane Mechanical Response and Mechanoporation Damage under Deformation Simulations. Mol Biotechnol 2024; 66:865-875. [PMID: 37016179 DOI: 10.1007/s12033-023-00726-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 03/19/2023] [Indexed: 04/06/2023]
Abstract
Damage induced by transient disruption and mechanoporation in an intact cell membrane is a vital nanoscale biomechanical mechanism that critically affects cell viability. To complement experimental studies of mechanical membrane damage and disruption, molecular dynamics (MD) simulations have been performed at different force field resolutions, each of which follows different parameterization strategies and thus may influence the properties and dynamics of membrane systems. Therefore, the current study performed tensile deformation MD simulations of bilayer membranes using all-atom (AA), united-atom (UA), and coarse-grained Martini (CG-M) models to investigate how the damage biomechanics differs across atomistic and coarse-grained (CG) simulations. The mechanical response and mechanoporation damage were qualitatively similar but quantitatively different in the three models, including some progressive changes based on the coarse-graining level. The membranes yielded and reached ultimate strength at similar strains; however, the coarser systems exhibited lower average yield stresses and failure strains. The average failure strain in the UA model was approximately 7% lower than the AA, and the CG-M was 20% lower than UA and 27% lower than AA. The CG systems also nucleated a higher number of pores and larger pores, which resulted in higher damage during the deformation process. Overall, the study provides insight on the impact of force field-a critical factor in modeling biomolecular systems and their interactions-in inspecting membrane mechanosensitive responses and serves as a reference for justifying the appropriate force field for future studies of more complex membranes and more diverse biomolecular assemblies.
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Affiliation(s)
- Anh T N Vo
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, 200 Research Blvd, Starkville, MS, 39759, USA.
- Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, Starkville, MS, 39762, USA.
| | - Michael A Murphy
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, 200 Research Blvd, Starkville, MS, 39759, USA
| | - Phong K Phan
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, 200 Research Blvd, Starkville, MS, 39759, USA
- Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, Starkville, MS, 39762, USA
| | - Raj K Prabhu
- NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX, 77058, USA
| | - Tonya W Stone
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, 200 Research Blvd, Starkville, MS, 39759, USA
- Department of Mechanical Engineering, Mississippi State University, Mississippi State, Starkville, MS, 39762, USA
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2
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Li Y, Xiao W, Lin X. Long noncoding RNA MALAT1 inhibition attenuates sepsis-induced acute lung injury through modulating the miR-129-5p/PAX6/ZEB2 axis. Microbiol Immunol 2023; 67:142-153. [PMID: 36537561 DOI: 10.1111/1348-0421.13045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/05/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
This research aimed to investigate the role of the long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/microRNA-129-5p (miR-129-5p)/paired box gene 6 (PAX6) axis in sepsis-induced acute lung injury (ALI). MLE-12 cells and C57BL/6 mice were induced by LPS to establish lung injury in in vitro and in vivo models. Cell viability and apoptosis were measured by cell counting kit-8 assay and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) staining, respectively. Levels of inflammatory cytokines in cell supernatants and bronchoalveolar lavage fluid (BALF) were detected by ELISA. Lung injury was evaluated by lung wet weight-to-dry weight ratio and hematoxylin-eosin staining. MALAT1, PAX6, and zinc finger E-box-binding homeobox 2 (ZEB2) expression was elevated and miR-129-5p expression was reduced in the serum of patients with sepsis-induced ALI, LPS-induced MLE-12 cells, and lung tissues of ALI mice. MALAT1 interference delayed the LPS-induced cell proliferation decrease, apoptosis increase, and inflammatory factor increase. miR-129-5p inhibition could reverse the delaying effect of MALAT1 interference on LPS-induced lung cell injury. PAX6 overexpression (oe) reversed the inhibitory effect of miR-129-5p oe on LPS-induced lung cell injury. Downregulating MALAT1 reduced pulmonary edema, inflammatory cytokine levels, lung injury, and apoptosis in ALI mice. Moreover, miR-129-5p suppression or PAX6 oe reversed the delaying effect of MALAT1 interference on sepsis-induced ALI. MALAT1 aggravates sepsis-induced ALI via the miR-129-5p/PAX6/ZEB2 axis.
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Affiliation(s)
- Ying Li
- Department of Critical Care Medicine, The First Affiliated Hospital, Fujian Medical University, Fujian, Fuzhou, China
| | - Wenbiao Xiao
- Department of Critical Care Medicine, National Regional Medical Center, Binhai Campus of the First Affiliated Hospital, Fujian Medical University, Fujian, Fuzhou, China
| | - Xiao Lin
- Department of Critical Care Medicine, The First Affiliated Hospital, Fujian Medical University, Fujian, Fuzhou, China
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3
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Navarro-Hernandez IC, López-Ortega O, Acevedo-Ochoa E, Cervantes-Díaz R, Romero-Ramírez S, Sosa-Hernández VA, Meza-Sánchez DE, Juárez-Vega G, Pérez-Martínez CA, Chávez-Munguía B, Galván-Hernández A, Antillón A, Ortega-Blake I, Santos-Argumedo L, Hernández-Hernández JM, Maravillas-Montero JL. Tetraspanin 33 (TSPAN33) regulates endocytosis and migration of human B lymphocytes by affecting the tension of the plasma membrane. FEBS J 2020; 287:3449-3471. [PMID: 31958362 DOI: 10.1111/febs.15216] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 11/20/2019] [Accepted: 01/16/2020] [Indexed: 12/31/2022]
Abstract
B lymphocytes are a leukocyte subset capable of developing several functions apart from differentiating into antibody-secreting cells. These processes are triggered by external activation signals that induce changes in the plasma membrane properties, regulated by the formation of different lipid-bilayer subdomains that are associated with the underlying cytoskeleton through different linker molecules, thus allowing the functional specialization of regions within the membrane. Among these, there are tetraspanin-enriched domains. Tetraspanins constitute a superfamily of transmembrane proteins that establish lateral associations with other molecules, determining its activity and localization. In this study, we identified TSPAN33 as an active player during B-lymphocyte cytoskeleton and plasma membrane-related phenomena, including protrusion formation, adhesion, phagocytosis, and cell motility. By using an overexpression model of TSPAN33 in human Raji cells, we detected a specific distribution of this protein that includes membrane microvilli, the Golgi apparatus, and extracellular vesicles. Additionally, we identified diminished phagocytic ability and altered cell adhesion properties due to the aberrant expression of integrins. Accordingly, these cells presented an enhanced migratory phenotype, as shown by its augmented chemotaxis and invasion rates. When we evaluated the mechanic response of cells during fibronectin-induced spreading, we found that TSPAN33 expression inhibited changes in roughness and membrane tension. Contrariwise, TSPAN33 knockdown cells displayed opposite phenotypes to those observed in the overexpression model. Altogether, our data indicate that TSPAN33 represents a regulatory element of the adhesion and migration of B lymphocytes, suggesting a novel implication of this tetraspanin in the control of the mechanical properties of their plasma membrane.
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Affiliation(s)
- Itze C Navarro-Hernandez
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Orestes López-Ortega
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Ernesto Acevedo-Ochoa
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Unidad de Investigación Médica en Inmunoquímica, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, Mexico
| | - Rodrigo Cervantes-Díaz
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Facultad De Medicina, Universidad Nacional Autónoma De México, Mexico
| | - Sandra Romero-Ramírez
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Facultad De Medicina, Universidad Nacional Autónoma De México, Mexico
| | - Víctor A Sosa-Hernández
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico.,Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - David E Meza-Sánchez
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico
| | - Guillermo Juárez-Vega
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico
| | - César A Pérez-Martínez
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - Armando Antillón
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Iván Ortega-Blake
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Leopoldo Santos-Argumedo
- Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - José M Hernández-Hernández
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico
| | - José L Maravillas-Montero
- Red de Apoyo a la Investigación, Universidad Nacional Autónoma de México e Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico
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Galván-Hernández A, Kobayashi N, Hernández-Cobos J, Antillón A, Nakabayashi S, Ortega-Blake I. Morphology and dynamics of domains in ergosterol or cholesterol containing membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183101. [DOI: 10.1016/j.bbamem.2019.183101] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 10/02/2019] [Accepted: 10/24/2019] [Indexed: 12/19/2022]
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5
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Murphy MA, Mun S, Horstemeyer MF, Baskes MI, Bakhtiary A, LaPlaca MC, Gwaltney SR, Williams LN, Prabhu RK. Molecular dynamics simulations showing 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) membrane mechanoporation damage under different strain paths. J Biomol Struct Dyn 2018; 37:1346-1359. [DOI: 10.1080/07391102.2018.1453376] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- M. A. Murphy
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS, USA
- Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, MS, USA
| | - Sungkwang Mun
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS, USA
| | - M. F. Horstemeyer
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS, USA
- Department of Mechanical Engineering, Mississippi State University, Mississippi State, MS, USA
| | - M. I. Baskes
- Department of Aerospace Engineering, Mississippi State University, Mississippi State, MS, USA
- Los Alamos National Laboratory, Los Alamos, NM, USA
| | - A. Bakhtiary
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS, USA
- Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, MS, USA
| | - Michelle C. LaPlaca
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Steven R. Gwaltney
- Department of Chemistry, Mississippi State University, Mississippi State, MS 39762, USA
- Center for Computational Sciences, Mississippi State University, Mississippi State, MS 39762, USA
| | - Lakiesha N. Williams
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS, USA
- Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, MS, USA
| | - R. K. Prabhu
- Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS, USA
- Department of Agricultural and Biological Engineering, Mississippi State University, Mississippi State, MS, USA
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Augustyńska D, Burda K, Jemioła-Rzemińska M, Strzałka K. Temperature-dependent bifurcation of cooperative interactions in pure and enriched in β-carotene DPPC liposomes. Chem Biol Interact 2016; 256:236-48. [DOI: 10.1016/j.cbi.2016.07.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 06/17/2016] [Accepted: 07/11/2016] [Indexed: 11/16/2022]
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López-Ortega O, Ovalle-García E, Ortega-Blake I, Antillón A, Chávez-Munguía B, Patiño-López G, Fragoso-Soriano R, Santos-Argumedo L. Myo1g is an active player in maintaining cell stiffness in B-lymphocytes. Cytoskeleton (Hoboken) 2016; 73:258-68. [DOI: 10.1002/cm.21299] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 04/11/2016] [Accepted: 04/13/2016] [Indexed: 12/11/2022]
Affiliation(s)
- O. López-Ortega
- Departamento De Biomedicina Molecular; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
- Facultad De Medicina, Universidad Nacional Autónoma De México; Ciudad De México C. P. 04510 México
| | - E. Ovalle-García
- Universidad Autónoma De Nuevo León, UANL. Facultad De Ingeniería Mecánica Y Eléctrica, Av. Universidad S/N, Ciudad Universitaria, San Nicolás De Los Garza; Nuevo León C. P. 66451 México
| | - I. Ortega-Blake
- Instituto De Ciencias Físicas, UNAM; Cuernavaca Morelos C. P. 62210 México
| | - A. Antillón
- Instituto De Ciencias Físicas, UNAM; Cuernavaca Morelos C. P. 62210 México
| | - B. Chávez-Munguía
- Departamento De Infectómica Y Patogénesis Molecular; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
| | - G. Patiño-López
- Laboratorio De Investigación En Inmunología Y Proteómica, Hospital Infantil De México, “Federico Gómez”; Ciudad De México C. P. 06720 México
| | - R. Fragoso-Soriano
- Departamento De Física; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
| | - L. Santos-Argumedo
- Departamento De Biomedicina Molecular; Centro De Investigación Y De Estudios Avanzados Del Instituto Politécnico Nacional; Ciudad De México C. P. 07360 México
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Li Y, Zhu C, Zhu J, Liang H, Chen D, Zhao H, Liu B. Nanomechanics of phospholipid LB film studied layer by layer with AFM. Chem Cent J 2014; 8:71. [PMID: 25614761 PMCID: PMC4279057 DOI: 10.1186/s13065-014-0071-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 11/11/2014] [Indexed: 11/21/2022] Open
Abstract
Background Phospholipid, a main component of cell membrane, has been explored as a model system of the cell membrane and temporary scaffold materials in recent studies. The mechanical properties of phospholipid layers are essentially interesting since it is involved in several biological processes. Results Here, the nanomechanical properties such as indentation force, adhesion force and DMT (Derjaguin-Müller-Toporov) modulus of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) Langmuir-Blodgett (LB) films were analyzed layer by layer with Atomic Force Microscope (AFM) under deionized water condition. Conclusions The penetration distances in the indentation force curves are equal to the thicknesses of phospholipid films, and the yield forces of DSPC LB films in deionized water are smaller than that of similar lipid films in buffered solutions due to the influence of ions. Moreover, the DMT modulus of upper layer DSPC LB film is different from that of monolayer DSPC LB film due to the influence of their different substrates. Our results suggest that environment such as surrounding ions and substrate will strongly influence the measured nano-mechanical properties of the lipid bilayer, especially that of the down layer. A process about the exploration of nanomechanics of DSPC LB film. ![]()
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Affiliation(s)
- Yinli Li
- Institute of Photo-biophysics, School of Physics and Electronic, Henan University, Kaifeng, 475004 Henan PR China
| | - Changjiang Zhu
- College of Software, Henan University, Kaifeng, 475004 Henan PR China
| | - Jichun Zhu
- Institute of Photo-biophysics, School of Physics and Electronic, Henan University, Kaifeng, 475004 Henan PR China
| | - Hao Liang
- Institute of Photo-biophysics, School of Physics and Electronic, Henan University, Kaifeng, 475004 Henan PR China
| | - Dong Chen
- Institute of Photo-biophysics, School of Physics and Electronic, Henan University, Kaifeng, 475004 Henan PR China
| | - Huiling Zhao
- Institute of Photo-biophysics, School of Physics and Electronic, Henan University, Kaifeng, 475004 Henan PR China
| | - Bo Liu
- Institute of Photo-biophysics, School of Physics and Electronic, Henan University, Kaifeng, 475004 Henan PR China
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Louw TM, Budhiraja G, Viljoen HJ, Subramanian A. Mechanotransduction of ultrasound is frequency dependent below the cavitation threshold. ULTRASOUND IN MEDICINE & BIOLOGY 2013; 39:1303-19. [PMID: 23562015 PMCID: PMC4183372 DOI: 10.1016/j.ultrasmedbio.2013.01.015] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 01/18/2013] [Accepted: 01/27/2013] [Indexed: 05/11/2023]
Abstract
This study provides evidence that low-intensity ultrasound directly affects nuclear processes, and the magnitude of the effect varies with frequency. In particular, we show that the transcriptional induction of first load-inducible genes, which is independent of new protein synthesis, is frequency dependent. Bovine chondrocytes were exposed to low-intensity (below the cavitational threshold) ultrasound at 2, 5 and 8 MHz. Ultrasound elevated the expression of early response genes c-Fos, c-Jun and c-Myc, maximized at 5 MHz. The phosphorylated ERK inhibitor PD98059 abrogated any increase in c-series gene expression, suggesting that signaling occurs via the MAPPK/ERK pathway. However, phosphorylated ERK levels did not change with ultrasound frequency, indicating that processes downstream of ERK phosphorylation (such as nuclear transport and chromatin reorganization) respond to ultrasound with frequency dependence. A quantitative, biphasic mathematical model based on Biot theory predicted that cytoplasmic and nuclear stress is maximized at 5.2 ± 0.8 MHz for a chondrocyte, confirming experimental measurements.
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Affiliation(s)
- Tobias M Louw
- Department of Chemical & Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA
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Barrow E, Nicola AV, Liu J. Multiscale perspectives of virus entry via endocytosis. Virol J 2013; 10:177. [PMID: 23734580 PMCID: PMC3679726 DOI: 10.1186/1743-422x-10-177] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Accepted: 05/24/2013] [Indexed: 01/01/2023] Open
Abstract
Most viruses take advantage of endocytic pathways to gain entry into host cells and initiate infections. Understanding of virus entry via endocytosis is critically important for the design of antiviral strategies. Virus entry via endocytosis is a complex process involving hundreds of cellular proteins. The entire process is dictated by events occurring at multiple time and length scales. In this review, we discuss and evaluate the available means to investigate virus endocytic entry, from both experimental and theoretical/numerical modeling fronts, and highlight the importance of multiscale features. The complexity of the process requires investigations at a systems biology level, which involves the combination of different experimental approaches, the collaboration of experimentalists and theorists across different disciplines, and the development of novel multiscale models.
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Affiliation(s)
- Eric Barrow
- School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA
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Abstract
Lipid bilayers are natural barriers of biological cells and cellular compartments. Membrane proteins integrated in biological membranes enable vital cell functions such as signal transduction and the transport of ions or small molecules. In order to determine the activity of a protein of interest at defined conditions, the membrane protein has to be integrated into artificial lipid bilayers immobilized on a surface. For the fabrication of such biosensors expertise is required in material science, surface and analytical chemistry, molecular biology and biotechnology. Specifically, techniques are needed for structuring surfaces in the micro- and nanometer scale, chemical modification and analysis, lipid bilayer formation, protein expression, purification and solubilization, and most importantly, protein integration into engineered lipid bilayers. Electrochemical and optical methods are suitable to detect membrane activity-related signals. The importance of structural knowledge to understand membrane protein function is obvious. Presently only a few structures of membrane proteins are solved at atomic resolution. Functional assays together with known structures of individual membrane proteins will contribute to a better understanding of vital biological processes occurring at biological membranes. Such assays will be utilized in the discovery of drugs, since membrane proteins are major drug targets.
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Kocun M, Janshoff A. Pulling tethers from pore-spanning bilayers: towards simultaneous determination of local bending modulus and lateral tension of membranes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2012; 8:847-51. [PMID: 22228680 DOI: 10.1002/smll.201101557] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 10/31/2011] [Indexed: 05/16/2023]
Affiliation(s)
- Marta Kocun
- Institute of Physical Chemistry, University of Goettingen, Tammannstr. 6, 37077 Goettingen, Germany
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13
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Mey I, Steinem C, Janshoff A. Biomimetic functionalization of porous substrates: towards model systems for cellular membranes. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm31737k] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Huang CH, Hsiao PY, Tseng FG, Fan SK, Fu CC, Pan RL. Pore-spanning lipid membrane under indentation by a probe tip: a molecular dynamics simulation study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:11930-42. [PMID: 21859109 DOI: 10.1021/la201977d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We study the indentation of a free-standing lipid membrane suspended over a nanopore on a hydrophobic substrate by means of molecular dynamics simulations. We find that in the course of indentation the membrane bends at the point of contact and the fringes of the membrane glide downward intermittently along the pore edges and stop gliding when the fringes reach the edge bottoms. The bending continues afterward, and the large strain eventually induces a phase transition in the membrane, transformed from a bilayered structure to an interdigitated structure. The membrane is finally ruptured when the indentation goes deep enough. Several local physical quantities in the pore regions are calculated, which include the tilt angle of lipid molecules, the nematic order, the included angle, and the distance between neighboring lipids. The variations of these quantities reveal many detailed, not-yet-specified local structural transitions of lipid molecules under indentation. The force-indentation curve is also studied and discussed. The results make a connection between the microscopic structure and the macroscopic properties and provide deep insight into the understanding of the stability of a lipid membrane spanning over nanopore.
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Affiliation(s)
- Chen-Hsi Huang
- Department of Engineering and System Science, National Tsing Hua University, Taiwan, Republic of China
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