1
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Matsuki Y, Takashima M, Ueki M, Iwamoto M, Oiki S. Probing membrane deformation energy by KcsA potassium channel gating under varied membrane thickness and tension. FEBS Lett 2024. [PMID: 38880762 DOI: 10.1002/1873-3468.14956] [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: 04/19/2024] [Revised: 05/23/2024] [Accepted: 05/24/2024] [Indexed: 06/18/2024]
Abstract
This study investigated how membrane thickness and tension modify the gating of KcsA potassium channels when simultaneously varied. The KcsA channel undergoes global conformational changes upon gating: expansion of the cross-sectional area and longitudinal shortening upon opening. Thus, membranes impose differential effects on the open and closed conformations, such as hydrophobic mismatches. Here, the single-channel open probability was recorded in the contact bubble bilayer, by which variable thickness membranes under a defined tension were applied. A fully open channel in thin membranes turned to sporadic openings in thick membranes, where the channel responded moderately to tension increase. Quantitative gating analysis prompted the hypothesis that tension augmented the membrane deformation energy when hydrophobic mismatch was enhanced in thick membranes.
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Affiliation(s)
- Yuka Matsuki
- Department of Anesthesiology and Reanimatology, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Japan
- Life Science Innovation Center, University of Fukui, Yoshida-gun, Japan
| | - Masako Takashima
- Department of Molecular Neuroscience, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Japan
| | - Misuzu Ueki
- Life Science Innovation Center, University of Fukui, Yoshida-gun, Japan
- Department of Molecular Neuroscience, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Japan
| | - Masayuki Iwamoto
- Life Science Innovation Center, University of Fukui, Yoshida-gun, Japan
- Department of Molecular Neuroscience, Faculty of Medical Sciences, University of Fukui, Yoshida-gun, Japan
| | - Shigetoshi Oiki
- Biomedical Imaging Research Center, University of Fukui, Yoshida-gun, Japan
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2
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Park I, Choi S, Gwak Y, Kim J, Min G, Lim D, Lee SW. Microfluidic Electroporation Arrays for Investigating Electroporation-Induced Cellular Rupture Dynamics. BIOSENSORS 2024; 14:242. [PMID: 38785716 PMCID: PMC11118139 DOI: 10.3390/bios14050242] [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: 03/02/2024] [Revised: 05/01/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024]
Abstract
Electroporation is pivotal in bioelectrochemistry for cellular manipulation, with prominent applications in drug delivery and cell membrane studies. A comprehensive understanding of pore generation requires an in-depth analysis of the critical pore size and the corresponding energy barrier at the onset of cell rupture. However, many studies have been limited to basic models such as artificial membranes or theoretical simulations. Challenging this paradigm, our study pioneers using a microfluidic electroporation chip array. This tool subjects live breast cancer cell species to a diverse spectrum of alternating current electric field conditions, driving electroporation-induced cell rupture. We conclusively determined the rupture voltages across varying applied voltage loading rates, enabling an unprecedented characterization of electric cell rupture dynamics encompassing critical pore radius and energy barrier. Further bolstering our investigation, we probed cells subjected to cholesterol depletion via methyl-β-cyclodextrin and revealed a strong correlation with electroporation. This work not only elucidates the dynamics of electric rupture in live cell membranes but also sets a robust foundation for future explorations into the mechanisms and energetics of live cell electroporation.
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Affiliation(s)
- Insu Park
- Department of Biomedical Engineering, Konyang University, Daejeon 35365, Republic of Korea; (I.P.)
| | - Seungyeop Choi
- School of Biomedical Engineering, Korea University, Seoul 02481, Republic of Korea;
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
- BK21 Four Institute of Precision Public Health, Korea University, Seoul 02841, Republic of Korea
| | - Youngwoo Gwak
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Jingwon Kim
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Gyeongjun Min
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
| | - Danyou Lim
- Department of Biomedical Engineering, Konyang University, Daejeon 35365, Republic of Korea; (I.P.)
| | - Sang Woo Lee
- Department of Biomedical Engineering, Yonsei University, Wonju 26493, Republic of Korea
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3
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Raczyński P, Górny K, Bełdowski P, Marciniak B, Pöschel T, Dendzik Z. Influence of silicon nanocone on cell membrane self-sealing capabilities for targeted drug delivery-Computer simulation study. Arch Biochem Biophys 2023; 749:109802. [PMID: 37913856 DOI: 10.1016/j.abb.2023.109802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 10/06/2023] [Accepted: 10/27/2023] [Indexed: 11/03/2023]
Abstract
Efficient and non-invasive techniques of cargo delivery to biological cells are the focus of biomedical research because of their great potential importance for targeted drug therapy. Therefore, much effort is being made to study the characteristics of using nano-based biocompatible materials as systems that can facilitate this task while ensuring appropriate self-sealing of the cell membrane. Here, we study the effects of indentation and withdrawal of nanocone on phospholipid membrane by applying steered molecular dynamics (SMD) technique. Our results show that the withdrawal process directly depends on the initial position of the nanocone. The average force and work are considerably more significant in case of the withdrawal starting from a larger depth. This result is attributed to stronger hydrophobic interactions between the nanocone and lipid tails of the membrane molecules. Furthermore, when the indenter was started from the lower initial depth, the number of lipids removed from the membrane was several times smaller than the deeper indentation. The choice of the least invasive method for nanostructure-assisted drug delivery is crucial for possible applications in medicine. Therefore, the results presented in this work might be helpful in efficient and safe drug delivery with nanomaterials.
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Affiliation(s)
- Przemysław Raczyński
- University of Silesia in Katowice, Faculty of Science and Technology, 75 Pułku Piechoty 1A, Chorzów, 41-500, Poland.
| | - Krzysztof Górny
- University of Silesia in Katowice, Faculty of Science and Technology, 75 Pułku Piechoty 1A, Chorzów, 41-500, Poland
| | - Piotr Bełdowski
- School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, Surface and Corrosion Science, KTH Royal Institute of Technology, Drottning Kristinas Väg 51, Stockholm, SE-10044, Sweden; Institute of Mathematics and Physics, UTP University of Science and Technology, Bydgoszcz, 85-796, Poland
| | - Beata Marciniak
- Faculty of Telecommunications, Computer Science and Electrical Engineering, UTP University of Science and Technology, Bydgoszcz, 85-796, Poland
| | - Thorsten Pöschel
- Institute for Multiscale Simulation, Friedrich-Alexander-Universität Erlangen-Nürnber, IZNF Cauerstraße 3, Erlangen, 91058, Germany
| | - Zbigniew Dendzik
- University of Silesia in Katowice, Faculty of Science and Technology, 75 Pułku Piechoty 1A, Chorzów, 41-500, Poland
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4
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Stability of supported hybrid lipid bilayers on chemically and topographically-modified surfaces. Colloids Surf A Physicochem Eng Asp 2023. [DOI: 10.1016/j.colsurfa.2023.131125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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5
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Zabala-Ferrera O, Liu P, Beltramo PJ. Determining the Bending Rigidity of Free-Standing Planar Phospholipid Bilayers. MEMBRANES 2023; 13:129. [PMID: 36837632 PMCID: PMC9959114 DOI: 10.3390/membranes13020129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/14/2023] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
We describe a method to determine membrane bending rigidity from capacitance measurements on large area, free-standing, planar, biomembranes. The bending rigidity of lipid membranes is an important biological mechanical property that is commonly optically measured in vesicles, but difficult to quantify in a planar, unsupported system. To accomplish this, we simultaneously image and apply an electric potential to free-standing, millimeter area, planar lipid bilayers composed of DOPC and DOPG phospholipids to measure the membrane Young's (elasticity) modulus. The bilayer is then modeled as two adjacent thin elastic films to calculate bending rigidity from the electromechanical response of the membrane to the applied field. Using DOPC, we show that bending rigidities determined by this approach are in good agreement with the existing work using neutron spin echo on vesicles, atomic force spectroscopy on supported lipid bilayers, and micropipette aspiration of giant unilamellar vesicles. We study the effect of asymmetric calcium concentration on symmetric DOPC and DOPG membranes and quantify the resulting changes in bending rigidity. This platform offers the ability to create planar bilayers of controlled lipid composition and aqueous ionic environment, with the ability to asymmetrically alter both. We aim to leverage this high degree of compositional and environmental control, along with the capacity to measure physical properties, in the study of various biological processes in the future.
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6
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Mechanical signatures of human colon cancers. Sci Rep 2022; 12:12475. [PMID: 35864200 PMCID: PMC9304395 DOI: 10.1038/s41598-022-16669-3] [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: 03/22/2022] [Accepted: 07/13/2022] [Indexed: 11/26/2022] Open
Abstract
Besides the standard parameters used for colorectal cancer (CRC) management, new features are needed in clinical practice to improve progression-free and overall survival. In some cancers, the microenvironment mechanical properties can contribute to cancer progression and metastasis formation, or constitute a physical barrier for drug penetration or immune cell infiltration. These mechanical properties remain poorly known for colon tissues. Using a multidisciplinary approach including clinical data, physics and geostatistics, we characterized the stiffness of healthy and malignant colon specimens. For this purpose, we analyzed a prospective cohort of 18 patients with untreated colon adenocarcinoma using atomic force microscopy to generate micrometer-scale mechanical maps. We characterized the stiffness of normal epithelium samples taken far away or close to the tumor area and selected tumor tissue areas. These data showed that normal epithelium was softer than tumors. In tumors, stroma areas were stiffer than malignant epithelial cell areas. Among the clinical parameters, tumor left location, higher stage, and RAS mutations were associated with increased tissue stiffness. Thus, in patients with CRC, measuring tumor tissue rigidity may have a translational value and an impact on patient care.
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7
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Abou Karam P, Rosenhek‐Goldian I, Ziv T, Ben Ami Pilo H, Azuri I, Rivkin A, Kiper E, Rotkopf R, Cohen SR, Torrecilhas AC, Avinoam O, Rojas A, Morandi MI, Regev‐Rudzki N. Malaria parasites release vesicle subpopulations with signatures of different destinations. EMBO Rep 2022; 23:e54755. [PMID: 35642585 PMCID: PMC9253735 DOI: 10.15252/embr.202254755] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/02/2022] [Accepted: 05/11/2022] [Indexed: 11/09/2022] Open
Abstract
Malaria is the most serious mosquito-borne parasitic disease, caused mainly by the intracellular parasite Plasmodium falciparum. The parasite invades human red blood cells and releases extracellular vesicles (EVs) to alter its host responses. It becomes clear that EVs are generally composed of sub-populations. Seeking to identify EV subpopulations, we subject malaria-derived EVs to size-separation analysis, using asymmetric flow field-flow fractionation. Multi-technique analysis reveals surprising characteristics: we identify two distinct EV subpopulations differing in size and protein content. Small EVs are enriched in complement-system proteins and large EVs in proteasome subunits. We then measure the membrane fusion abilities of each subpopulation with three types of host cellular membranes: plasma, late and early endosome. Remarkably, small EVs fuse to early endosome liposomes at significantly greater levels than large EVs. Atomic force microscope imaging combined with machine-learning methods further emphasizes the difference in biophysical properties between the two subpopulations. These results shed light on the sophisticated mechanism by which malaria parasites utilize EV subpopulations as a communication tool to target different cellular destinations or host systems.
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Affiliation(s)
- Paula Abou Karam
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | | | - Tamar Ziv
- Smoler Proteomics CenterDepartment of BiologyTechnion – Israel Institute of TechnologyHaifaIsrael
| | - Hila Ben Ami Pilo
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Ido Azuri
- Bioinformatics UnitLife Sciences Core FacilitiesWeizmann Institute of ScienceRehovotIsrael
| | - Anna Rivkin
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Edo Kiper
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Ron Rotkopf
- Bioinformatics UnitLife Sciences Core FacilitiesWeizmann Institute of ScienceRehovotIsrael
| | - Sidney R Cohen
- Department of Chemical Research SupportWeizmann Institute of ScienceRehovotIsrael
| | | | - Ori Avinoam
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Alicia Rojas
- Laboratory of HelminthologyFaculty of MicrobiologyUniversity of Costa RicaSan JoséCosta Rica
| | - Mattia I Morandi
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
| | - Neta Regev‐Rudzki
- Department of Biomolecular SciencesWeizmann Institute of ScienceRehovotIsrael
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8
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Wagner AM, Eto H, Joseph A, Kohyama S, Haraszti T, Zamora RA, Vorobii M, Giannotti MI, Schwille P, Rodriguez-Emmenegger C. Dendrimersome Synthetic Cells Harbor Cell Division Machinery of Bacteria. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202364. [PMID: 35579491 DOI: 10.1002/adma.202202364] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/11/2022] [Indexed: 06/15/2023]
Abstract
The integration of active cell machinery with synthetic building blocks is the bridge toward developing synthetic cells with biological functions and beyond. Self-replication is one of the most important tasks of living systems, and various complex machineries exist to execute it. In Escherichia coli, a contractile division ring is positioned to mid-cell by concentration oscillations of self-organizing proteins (MinCDE), where it severs membrane and cell wall. So far, the reconstitution of any cell division machinery has exclusively been tied to liposomes. Here, the reconstitution of a rudimentary bacterial divisome in fully synthetic bicomponent dendrimersomes is shown. By tuning the membrane composition, the interaction of biological machinery with synthetic membranes can be tailored to reproduce its dynamic behavior. This constitutes an important breakthrough in the assembly of synthetic cells with biological elements, as tuning of membrane-divisome interactions is the key to engineering emergent biological behavior from the bottom-up.
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Affiliation(s)
- Anna M Wagner
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52074, Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074, Aachen, Germany
| | - Hiromune Eto
- Max Planck Institute of Biochemistry, Department of Cellular and Molecular Biophysics, Am Klopferspitz 18, 82152, Martinsried, Germany
| | - Anton Joseph
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52074, Aachen, Germany
- Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074, Aachen, Germany
| | - Shunshi Kohyama
- Max Planck Institute of Biochemistry, Department of Cellular and Molecular Biophysics, Am Klopferspitz 18, 82152, Martinsried, Germany
| | - Tamás Haraszti
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52074, Aachen, Germany
| | - Ricardo A Zamora
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Carrer de Baldiri Reixac 10-12, Barcelona, 08028, Spain
- Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, 28029, Spain
| | - Mariia Vorobii
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52074, Aachen, Germany
| | - Marina I Giannotti
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Carrer de Baldiri Reixac 10-12, Barcelona, 08028, Spain
- Network Biomedical Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Madrid, 28029, Spain
- University of Barcelona, Department of Materials Science and Physical Chemistry, Martí i Franquès 10, Barcelona, 08028, Spain
| | - Petra Schwille
- Max Planck Institute of Biochemistry, Department of Cellular and Molecular Biophysics, Am Klopferspitz 18, 82152, Martinsried, Germany
| | - Cesar Rodriguez-Emmenegger
- DWI-Leibniz Institute for Interactive Materials, Forckenbeckstraße 50, 52074, Aachen, Germany
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), Carrer de Baldiri Reixac 10-12, Barcelona, 08028, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, Barcelona, 08010, Spain
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9
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Schaefer KG, Pittman AE, Barrera FN, King GM. Atomic force microscopy for quantitative understanding of peptide-induced lipid bilayer remodeling. Methods 2022; 197:20-29. [PMID: 33164792 DOI: 10.1016/j.ymeth.2020.10.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/17/2020] [Accepted: 10/20/2020] [Indexed: 12/15/2022] Open
Abstract
A number of peptides are known to bind lipid bilayer membranes and cause these natural barriers to leak in an uncontrolled manner. Though membrane permeabilizing peptides play critical roles in cellular activity and may have promising future applications in the therapeutic arena, significant questions remain about their mechanisms of action. The atomic force microscope (AFM) is a single molecule imaging tool capable of addressing lipid bilayers in near-native fluid conditions. The apparatus complements traditional assays by providing local topographic maps of bilayer remodeling induced by membrane permeabilizing peptides. The information garnered from the AFM includes direct visualization and statistical analyses of distinct bilayer remodeling modes such as highly localized pore-like voids in the bilayer and dispersed thinned membrane regions. Colocalization of distinct remodeling modes can be studied. Here we examine recent work in the field and outline methods used to achieve precise AFM image data. Experimental challenges and common pitfalls are discussed as well as techniques for unbiased analysis including the Hessian blob detection algorithm, bootstrapping, and the Bayesian information criterion. When coupled with robust statistical analyses, high precision AFM data is poised to advance understanding of an important family of peptides that cause poration of membrane bilayers.
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Affiliation(s)
- K G Schaefer
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - A E Pittman
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - F N Barrera
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA
| | - G M King
- Department of Physics and Astronomy, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
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10
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Vázquez RF, Ovalle-García E, Antillón A, Ortega-Blake I, Muñoz-Garay C, Maté SM. Formation and Nanoscale Characterization of Asymmetric Supported Lipid Bilayers Containing Raft-Like Domains. Methods Mol Biol 2022; 2402:243-256. [PMID: 34854049 DOI: 10.1007/978-1-0716-1843-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The development of new strategies for achieving stable asymmetric membrane models has turned interleaflet lipid asymmetry into a topic of major interest. Cyclodextrin-mediated lipid exchange constitutes a simple and versatile method for preparing asymmetric membrane models without the need for sophisticated equipment. Here we describe a protocol for preparing asymmetric supported lipid bilayers mimicking membrane rafts by cyclodextrin-mediated lipid exchange and the main guidelines for obtaining structural information and quantitative measures of their mechanical properties using Atomic force microscopy and Force spectroscopy; two powerful techniques that allow membrane characterization at the nanoscale.
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Affiliation(s)
- Romina F Vázquez
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT-La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
- Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, La Plata, Argentina.
| | - Erasmo Ovalle-García
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Armando Antillón
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Iván Ortega-Blake
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Carlos Muñoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Cuernavaca, México
| | - Sabina M Maté
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT-La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
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11
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Botet-Carreras A, Montero MT, Sot J, Domènech Ò, Borrell JH. Engineering and development of model lipid membranes mimicking the HeLa cell membrane. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.127663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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12
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Ridolfi A, Caselli L, Baldoni M, Montis C, Mercuri F, Berti D, Valle F, Brucale M. Stiffness of Fluid and Gel Phase Lipid Nanovesicles: Weighting the Contributions of Membrane Bending Modulus and Luminal Pressurization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:12027-12037. [PMID: 34610740 DOI: 10.1021/acs.langmuir.1c01660] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The mechanical properties of biogenic membranous compartments are thought to be relevant in numerous biological processes; however, their quantitative measurement remains challenging for most of the already available force spectroscopy (FS)-based techniques. In particular, the debate on the mechanics of lipid nanovesicles and on the interpretation of their mechanical response to an applied force is still open. This is mostly due to the current lack of a unified model being able to describe the mechanical response of both gel and fluid phase lipid vesicles and to disentangle the contributions of membrane rigidity and luminal pressure. In this framework, we herein propose a simple model in which the interplay of membrane rigidity and luminal pressure to the overall vesicle stiffness is described as a series of springs; this approach allows estimating these two contributions for both gel and fluid phase liposomes. Atomic force microscopy-based FS, performed on both vesicles and supported lipid bilayers, is exploited for obtaining all the parameters involved in the model. Moreover, the use of coarse-grained full-scale molecular dynamics simulations allowed for better understanding of the differences in the mechanical responses of gel and fluid phase bilayers and supported the experimental findings. The results suggest that the pressure contribution is similar among all the probed vesicle types; however, it plays a dominant role in the mechanical response of lipid nanovesicles presenting a fluid phase membrane, while its contribution becomes comparable to the one of membrane rigidity in nanovesicles with a gel phase lipid membrane. The results presented herein offer a simple way to quantify two of the most important parameters in vesicle nanomechanics (membrane rigidity and internal pressurization), and as such represent a first step toward a currently unavailable, unified model for the mechanical response of gel and fluid phase lipid nanovesicles.
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Affiliation(s)
- Andrea Ridolfi
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Firenze, Italy
- Istituto per lo Studio dei Materiali Nanostrutturati, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
- Dipartimento di Chimica "Ugo Schiff", Università degli Studi di Firenze, 50019 Firenze, Italy
| | - Lucrezia Caselli
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Firenze, Italy
- Dipartimento di Chimica "Ugo Schiff", Università degli Studi di Firenze, 50019 Firenze, Italy
| | - Matteo Baldoni
- Istituto per lo Studio dei Materiali Nanostrutturati, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
| | - Costanza Montis
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Firenze, Italy
- Dipartimento di Chimica "Ugo Schiff", Università degli Studi di Firenze, 50019 Firenze, Italy
| | - Francesco Mercuri
- Istituto per lo Studio dei Materiali Nanostrutturati, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
| | - Debora Berti
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Firenze, Italy
- Dipartimento di Chimica "Ugo Schiff", Università degli Studi di Firenze, 50019 Firenze, Italy
| | - Francesco Valle
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Firenze, Italy
- Istituto per lo Studio dei Materiali Nanostrutturati, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
| | - Marco Brucale
- Consorzio Interuniversitario per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Firenze, Italy
- Istituto per lo Studio dei Materiali Nanostrutturati, Consiglio Nazionale delle Ricerche, 40129 Bologna, Italy
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13
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Azouz M, Feuillie C, Lafleur M, Molinari M, Lecomte S. Interaction of Tau construct K18 with model lipid membranes. NANOSCALE ADVANCES 2021; 3:4244-4253. [PMID: 36132846 PMCID: PMC9417262 DOI: 10.1039/d1na00055a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 06/16/2021] [Indexed: 06/12/2023]
Abstract
One of the hallmarks of Alzheimer's disease (AD) is the formation of neurofibrillary tangles, resulting from the aggregation of the tubulin associated unit protein (Tau), which holds a vital role in maintaining neuron integrity in a healthy brain. The development of such aggregates and their deposition in the brain seem to correlate with the onset of neurodegeneration processes. The misfolding and subsequent aggregation of the protein into paired helical filaments that further form the tangles, lead to dysfunction of the protein with neuronal loss and cognitive decline. The aggregation of the protein then seems to be a causative factor of the neurodegeneration associated with AD. The hypothesis of an involvement of the membrane in modulating the misfolding and assembly of Tau into paired helical filaments attracts increasing interests. To provide more insight about how lipids can modulate the interactions with Tau, we have conducted a comprehensive Atomic Force Microscopy (AFM) study involving supported lipid bilayers of controlled compositions with the Tau microtubule-binding construct K18. Particularly, the effects of zwitterionic and negatively charged phospholipids on the interaction have been investigated. Deleterious solubilization effects have been evidenced on fluid zwitterionic membranes as well as an inability of K18 to fragment gel phases. The role of negative lipids in the aggregation of the peptide and the particular ability of phosphatidylinositol-4,5-bisphosphate (PIP2) in inducing K18 fibrillization on membranes are also reported.
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Affiliation(s)
- Mehdi Azouz
- Institute of Chemistry and Biology of Membranes and Nano-Objects, CNRS, Université de Bordeaux, INP Bordeaux, UMR5248 allée Geoffroy Saint Hilaire 33600 Pessac France
- Department of Chemistry, Université de Montréal Succursale Centre-Ville Montréal C.P. 6128 Québec Canada H3C 3J7
| | - Cécile Feuillie
- Institute of Chemistry and Biology of Membranes and Nano-Objects, CNRS, Université de Bordeaux, INP Bordeaux, UMR5248 allée Geoffroy Saint Hilaire 33600 Pessac France
| | - Michel Lafleur
- Department of Chemistry, Université de Montréal Succursale Centre-Ville Montréal C.P. 6128 Québec Canada H3C 3J7
| | - Michaël Molinari
- Institute of Chemistry and Biology of Membranes and Nano-Objects, CNRS, Université de Bordeaux, INP Bordeaux, UMR5248 allée Geoffroy Saint Hilaire 33600 Pessac France
| | - Sophie Lecomte
- Institute of Chemistry and Biology of Membranes and Nano-Objects, CNRS, Université de Bordeaux, INP Bordeaux, UMR5248 allée Geoffroy Saint Hilaire 33600 Pessac France
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14
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Ordas L, Costa L, Lozano A, Chevillard C, Calovoulos A, Kantar D, Fernandez L, Chauvin L, Dosset P, Doucet C, Heron-Milhavet L, Odintsova E, Berditchevski F, Milhiet PE, Bénistant C. Mechanical Control of Cell Migration by the Metastasis Suppressor Tetraspanin CD82/KAI1. Cells 2021; 10:cells10061545. [PMID: 34207462 PMCID: PMC8234748 DOI: 10.3390/cells10061545] [Citation(s) in RCA: 3] [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: 04/06/2021] [Revised: 06/10/2021] [Accepted: 06/15/2021] [Indexed: 01/16/2023] Open
Abstract
The plasma membrane is a key actor of cell migration. For instance, its tension controls persistent cell migration and cell surface caveolae integrity. Then, caveolae constituents such as caveolin-1 can initiate a mechanotransduction loop that involves actin- and focal adhesion-dependent control of the mechanosensor YAP to finely tune cell migration. Tetraspanin CD82 (also named KAI-1) is an integral membrane protein and a metastasis suppressor. Its expression is lost in many cancers including breast cancer. It is a strong inhibitor of cell migration by a little-known mechanism. We demonstrated here that CD82 controls persistent 2D migration of EGF-induced single cells, stress fibers and focal adhesion sizes and dynamics. Mechanistically, we found that CD82 regulates membrane tension, cell surface caveolae abundance and YAP nuclear translocation in a caveolin-1-dependent manner. Altogether, our data show that CD82 controls 2D cell migration using membrane-driven mechanics involving caveolin and the YAP pathway.
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Affiliation(s)
- Laura Ordas
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
| | - Luca Costa
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
| | - Anthony Lozano
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
- Institut de Génétique Moléculaire de Montpellier, University Montpellier, CNRS, 34293 Montpellier, France
| | - Christopher Chevillard
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
| | - Alexia Calovoulos
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
| | - Diala Kantar
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194—University Montpellier—Institut Régional du Cancer de Montpellier (ICM), 34298 Montpellier, France; (D.K.); (L.H.-M.)
| | - Laurent Fernandez
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
- European Institute of Chemistry and Biology (IECB), University of Bordeaux, 33607 Pessac, France
| | - Lucie Chauvin
- Centre de Recherche de Biologie Cellulaire de Montpellier (CRBM), CNRS UMR 5237, University Montpellier, 34293 Montpellier, France;
| | - Patrice Dosset
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
| | - Christine Doucet
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
| | - Lisa Heron-Milhavet
- Institut de Recherche en Cancérologie de Montpellier (IRCM), Inserm U1194—University Montpellier—Institut Régional du Cancer de Montpellier (ICM), 34298 Montpellier, France; (D.K.); (L.H.-M.)
| | - Elena Odintsova
- Institute of Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (E.O.); (F.B.)
| | - Fedor Berditchevski
- Institute of Cancer and Genomic Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK; (E.O.); (F.B.)
| | - Pierre-Emmanuel Milhiet
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
- Correspondence: (P.-E.M.); (C.B.)
| | - Christine Bénistant
- Centre de Biologie Structurale (CBS), CNRS, INSERM, University Montpellier, 34090 Montpellier, France; (L.O.); (L.C.); (A.L.); (C.C.); (A.C.); (L.F.); (P.D.); (C.D.)
- Correspondence: (P.-E.M.); (C.B.)
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15
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MAGI1 inhibits the AMOTL2/p38 stress pathway and prevents luminal breast tumorigenesis. Sci Rep 2021; 11:5752. [PMID: 33707576 PMCID: PMC7952706 DOI: 10.1038/s41598-021-85056-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 02/24/2021] [Indexed: 02/08/2023] Open
Abstract
Alterations to cell polarization or to intercellular junctions are often associated with epithelial cancer progression, including breast cancers (BCa). We show here that the loss of the junctional scaffold protein MAGI1 is associated with bad prognosis in luminal BCa, and promotes tumorigenesis. E-cadherin and the actin binding scaffold AMOTL2 accumulate in MAGI1 deficient cells which are subjected to increased stiffness. These alterations are associated with low YAP activity, the terminal Hippo-pathway effector, but with an elevated ROCK and p38 Stress Activated Protein Kinase activities. Blocking ROCK prevented p38 activation, suggesting that MAGI1 limits p38 activity in part through releasing actin strength. Importantly, the increased tumorigenicity of MAGI1 deficient cells is rescued in the absence of AMOTL2 or after inhibition of p38, demonstrating that MAGI1 acts as a tumor-suppressor in luminal BCa by inhibiting an AMOTL2/p38 stress pathway.
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16
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Verbeek SF, Awasthi N, Teiwes NK, Mey I, Hub JS, Janshoff A. How arginine derivatives alter the stability of lipid membranes: dissecting the roles of side chains, backbone and termini. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2021; 50:127-142. [PMID: 33661339 PMCID: PMC8071801 DOI: 10.1007/s00249-021-01503-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 01/08/2021] [Accepted: 01/19/2021] [Indexed: 12/22/2022]
Abstract
Arginine (R)-rich peptides constitute the most relevant class of cell-penetrating peptides and other membrane-active peptides that can translocate across the cell membrane or generate defects in lipid bilayers such as water-filled pores. The mode of action of R-rich peptides remains a topic of controversy, mainly because a quantitative and energetic understanding of arginine effects on membrane stability is lacking. Here, we explore the ability of several oligo-arginines R[Formula: see text] and of an arginine side chain mimic R[Formula: see text] to induce pore formation in lipid bilayers employing MD simulations, free-energy calculations, breakthrough force spectroscopy and leakage assays. Our experiments reveal that R[Formula: see text] but not R[Formula: see text] reduces the line tension of a membrane with anionic lipids. While R[Formula: see text] peptides form a layer on top of a partly negatively charged lipid bilayer, R[Formula: see text] leads to its disintegration. Complementary, our simulations show R[Formula: see text] causes membrane thinning and area per lipid increase beside lowering the pore nucleation free energy. Model polyarginine R[Formula: see text] similarly promoted pore formation in simulations, but without overall bilayer destabilization. We conclude that while the guanidine moiety is intrinsically membrane-disruptive, poly-arginines favor pore formation in negatively charged membranes via a different mechanism. Pore formation by R-rich peptides seems to be counteracted by lipids with PC headgroups. We found that long R[Formula: see text] and R[Formula: see text] but not short R[Formula: see text] reduce the free energy of nucleating a pore. In short R[Formula: see text], the substantial effect of the charged termini prevent their membrane activity, rationalizing why only longer [Formula: see text] are membrane-active.
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Affiliation(s)
- Sarah F Verbeek
- Department of Chemistry, Institute of Physical Chemistry, Georg-August-Universität Göttingen, 37077, Göttingen, Germany
| | - Neha Awasthi
- Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, 37077, Göttingen, Germany
| | - Nikolas K Teiwes
- Department of Chemistry, Institute of Physical Chemistry, Georg-August-Universität Göttingen, 37077, Göttingen, Germany
| | - Ingo Mey
- Department of Chemistry, Institute of Physical Chemistry, Georg-August-Universität Göttingen, 37077, Göttingen, Germany
| | - Jochen S Hub
- Institute of Microbiology and Genetics, Georg-August-Universität Göttingen, 37077, Göttingen, Germany. .,Theoretical Physics and Center for Biophyics, Saarland University, 66123, Saarbrücken, Germany.
| | - Andreas Janshoff
- Department of Chemistry, Institute of Physical Chemistry, Georg-August-Universität Göttingen, 37077, Göttingen, Germany
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17
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Eid J, Greige-Gerges H, Monticelli L, Jraij A. Elastic moduli of lipid membranes: Reproducibility of AFM measures. Chem Phys Lipids 2020; 234:105011. [PMID: 33217391 DOI: 10.1016/j.chemphyslip.2020.105011] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 10/26/2020] [Accepted: 11/15/2020] [Indexed: 11/29/2022]
Abstract
Membrane elastic properties play a major role in membrane remodeling events, such as vesicle fusion and fission. They are also crucial in drug delivery by liposomes. Different experimental techniques are available to measure elastic properties. Among them, atomic force microscopy (AFM) presents the unique advantage of being directly applicable to nano-sized liposomes. Unfortunately, different AFM measures reported in the literature show little agreement among each other and are difficult to compare with measures of bending modulus obtained by other experimental techniques or by molecular simulations. In this work we determine the bending rigidity of Egg PC liposomes in terms of Young modulus via AFM measurements, using two different tip shapes and different cantilever force constants. We interpret the measures using the Hertz and Shell models, and observe a clear dependency of the Young modulus values on the tip properties and on the interpretative theory. The effect of the AFM tip shape is less important than the effect of the cantilever force constant, and the mathematical model has a major effect on the interpretation of the data. The Shell theory provides the closest agreement between AFM data and other experimental data for the membrane bending modulus. Finally, we compare the results to calculations of bending modulus from molecular dynamics simulations of membrane buckles. Simulations provide values of bending modulus consistent with literature data, but the agreement with AFM experiments is reasonable only for some specific experimental conditions.
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Affiliation(s)
- Jad Eid
- Bioactive Molecules Research Laboratory, Doctoral School of Sciences and Technologies, Faculty of Sciences, Lebanese University, Lebanon; Molecular Microbiology and Structural Biochemistry (MMSB), UMR 5086 CNRS / University Claude Bernard Lyon1, Lyon, France
| | - Hélène Greige-Gerges
- Bioactive Molecules Research Laboratory, Doctoral School of Sciences and Technologies, Faculty of Sciences, Lebanese University, Lebanon
| | - Luca Monticelli
- Molecular Microbiology and Structural Biochemistry (MMSB), UMR 5086 CNRS / University Claude Bernard Lyon1, Lyon, France
| | - Alia Jraij
- Bioactive Molecules Research Laboratory, Doctoral School of Sciences and Technologies, Faculty of Sciences, Lebanese University, Lebanon.
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18
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Vázquez RF, Ovalle-García E, Antillón A, Ortega-Blake I, Bakás LS, Muñoz-Garay C, Maté SM. Asymmetric bilayers mimicking membrane rafts prepared by lipid exchange: Nanoscale characterization using AFM-Force spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183467. [PMID: 32871116 DOI: 10.1016/j.bbamem.2020.183467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 08/07/2020] [Accepted: 08/24/2020] [Indexed: 01/03/2023]
Abstract
Sphingolipids-enriched rafts domains are proposed to occur in plasma membranes and to mediate important cellular functions. Notwithstanding, the asymmetric transbilayer distribution of phospholipids that exists in the membrane confers the two leaflets different potentials to form lateral domains as next to no sphingolipids are present in the inner leaflet. How the physical properties of one leaflet can influence the properties of the other and its importance on signal transduction across the membrane are questions still unresolved. In this work, we combined AFM imaging and Force spectroscopy measurements to assess domain formation and to study the nanomechanical properties of asymmetric supported lipid bilayers (SLBs) mimicking membrane rafts. Asymmetric SLBs were formed by incorporating N-palmitoyl-sphingomyelin (16:0SM) into the outer leaflet of preformed 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC)/Cholesterol SLBs through methyl-β-cyclodextrin-mediated lipid exchange. Lipid domains were detected after incorporation of 16:0SM though their phase state varied from gel to liquid ordered (Lo) phase if the procedure was performed at 24 or 37 °C, respectively. When comparing symmetric and asymmetric Lo domains, differences in size and morphology were observed, with asymmetric domains being smaller and more interconnected. Both types of Lo domains showed similar mechanical stability in terms of rupture forces and Young's moduli. Notably, force curves in asymmetric domains presented two rupture events that could be attributed to the sequential rupture of a liquid disordered (Ld) and a Lo phase. Interleaflet coupling in asymmetric Lo domains could also be inferred from those measurements. The experimental approach outlined here would significantly enhance the applicability of membrane models.
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Affiliation(s)
- Romina F Vázquez
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT- La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, 60 y 120, 1900 La Plata, Argentina; Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata, Argentina.
| | - Erasmo Ovalle-García
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Armando Antillón
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Iván Ortega-Blake
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Laura S Bakás
- Centro de Investigación en Proteínas Vegetales (CIProVe), Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata, Argentina
| | - Carlos Muñoz-Garay
- Instituto de Ciencias Físicas, Universidad Nacional Autónoma de México, Av. Universidad 2001, Col. Chamilpa, 62210 Cuernavaca, México
| | - Sabina M Maté
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP), CCT- La Plata, CONICET, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, 60 y 120, 1900 La Plata, Argentina.
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