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Alimohamadi H, Luo EWC, Yang R, Gupta S, Nolden KA, Mandal T, Blake Hill R, Wong GCL. Dynamins combine mechano-constriction and membrane remodeling to enable two-step mitochondrial fission via a 'snap-through' instability. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.19.608723. [PMID: 39229060 PMCID: PMC11370335 DOI: 10.1101/2024.08.19.608723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Mitochondrial fission is controlled by dynamin proteins, the dysregulation of which is correlated with diverse diseases. Fission dynamins are GTP hydrolysis-driven mechanoenzymes that self-oligomerize into helical structures that constrict membrane to achieve fission, but details are not well understood. However, dynamins can also remodel membranes by inducing negative Gaussian curvature, the type of curvature required for completion of fission. Here, we examine how these drastically different mechanisms synergistically exert their influences on a membrane, via a mechanical model calibrated with small-angle X-ray scattering structural data. We find that free dynamin can trigger a "snap-through instability" that enforces a shape transition from an oligomer-confined cylindrical membrane to a drastically narrower catenoid-shaped neck within the spontaneous hemi-fission regime, in a manner that depends critically on the length of the confined tube. These results indicate how the combination of dynamin assembly, and paradoxically disassembly, can lead to diverse pathways to scission.
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Affiliation(s)
- Haleh Alimohamadi
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Elizabeth Wei-Chia Luo
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Rena Yang
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
| | - Shivam Gupta
- Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - Kelsey A Nolden
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Taraknath Mandal
- Department of Physics, Indian Institute of Technology Kanpur, Kanpur, 208016, India
| | - R Blake Hill
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
- Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, CO, 80045, USA
| | - Gerard C L Wong
- Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90025, USA
- Department of Chemistry and Biochemistry, University of California, Los Angeles, CA, 90095, USA
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- California NanoSystems Institute, University of California, Los Angeles, CA, 90095, USA
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Ghisleni A, Bonilla-Quintana M, Crestani M, Lavagnino Z, Galli C, Rangamani P, Gauthier NC. Mechanically induced topological transition of spectrin regulates its distribution in the mammalian cell cortex. Nat Commun 2024; 15:5711. [PMID: 38977673 PMCID: PMC11231315 DOI: 10.1038/s41467-024-49906-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 06/24/2024] [Indexed: 07/10/2024] Open
Abstract
The cell cortex is a dynamic assembly formed by the plasma membrane and underlying cytoskeleton. As the main determinant of cell shape, the cortex ensures its integrity during passive and active deformations by adapting cytoskeleton topologies through yet poorly understood mechanisms. The spectrin meshwork ensures such adaptation in erythrocytes and neurons by adopting different organizations. Erythrocytes rely on triangular-like lattices of spectrin tetramers, whereas in neurons they are organized in parallel, periodic arrays. Since spectrin is ubiquitously expressed, we exploited Expansion Microscopy to discover that, in fibroblasts, distinct meshwork densities co-exist. Through biophysical measurements and computational modeling, we show that the non-polarized spectrin meshwork, with the intervention of actomyosin, can dynamically transition into polarized clusters fenced by actin stress fibers that resemble periodic arrays as found in neurons. Clusters experience lower mechanical stress and turnover, despite displaying an extension close to the tetramer contour length. Our study sheds light on the adaptive properties of spectrin, which participates in the protection of the cell cortex by varying its densities in response to key mechanical features.
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Affiliation(s)
- Andrea Ghisleni
- IFOM ETS, The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Mayte Bonilla-Quintana
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, USA
| | - Michele Crestani
- IFOM ETS, The AIRC Institute of Molecular Oncology, Milan, Italy
- Laboratory of Applied Mechanobiology, Department for Health Sciences and Technology, ETH Zürich, Zürich, Switzerland
| | - Zeno Lavagnino
- IFOM ETS, The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Camilla Galli
- IFOM ETS, The AIRC Institute of Molecular Oncology, Milan, Italy
- Humanitas Cardio Center, IRCCS Humanitas Research Hospital, Rozzano (Milan, Italy
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA, USA.
| | - Nils C Gauthier
- IFOM ETS, The AIRC Institute of Molecular Oncology, Milan, Italy.
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Bonilla-Quintana M, Ghisleni A, Gauthier N, Rangamani P. Dynamic mechanisms for membrane skeleton transitions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.29.591779. [PMID: 38746295 PMCID: PMC11092671 DOI: 10.1101/2024.04.29.591779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The plasma membrane and the underlying skeleton form a protective barrier for eukaryotic cells. The molecules forming this complex composite material constantly rearrange under mechanical stress to confer this protective capacity. One of those molecules, spectrin, is ubiquitous in the membrane skeleton and primarily located proximal to the inner leaflet of the plasma membrane and engages in protein-lipid interactions via a set of membrane-anchoring domains. Spectrin is linked by short actin filaments and its conformation varies in different types of cells. In this work, we developed a generalized network model for the membrane skeleton integrated with myosin contractility and membrane mechanics to investigate the response of the spectrin meshwork to mechanical loading. We observed that the force generated by membrane bending is important to maintain a smooth skeletal structure. This suggests that the membrane is not just supported by the skeleton, but has an active contribution to the stability of the cell structure. We found that spectrin and myosin turnover are necessary for the transition between stress and rest states in the skeleton. Our model reveals that the actin-spectrin meshwork dynamics are balanced by the membrane forces with area constraint and volume restriction promoting the stability of the membrane skeleton. Furthermore, we showed that cell attachment to the substrate promotes shape stabilization. Thus, our proposed model gives insight into the shared mechanisms of the membrane skeleton associated with myosin and membrane that can be tested in different types of cells.
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Affiliation(s)
- M. Bonilla-Quintana
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla CA 92093, USA
| | - A. Ghisleni
- Institute FIRC of Molecular Oncology (IFOM), Via Adamello 16, 20139, Milan, Italy
| | - N. Gauthier
- Institute FIRC of Molecular Oncology (IFOM), Via Adamello 16, 20139, Milan, Italy
| | - P. Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla CA 92093, USA
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Alimohamadi H, Rangamani P. Effective cell membrane tension protects red blood cells against malaria invasion. PLoS Comput Biol 2023; 19:e1011694. [PMID: 38048346 PMCID: PMC10721198 DOI: 10.1371/journal.pcbi.1011694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 12/14/2023] [Accepted: 11/16/2023] [Indexed: 12/06/2023] Open
Abstract
A critical step in how malaria parasites invade red blood cells (RBCs) is the wrapping of the membrane around the egg-shaped merozoites. Recent experiments have revealed that RBCs can be protected from malaria invasion by high membrane tension. While cellular and biochemical aspects of parasite actomyosin motor forces during the malaria invasion have been well studied, the important role of the biophysical forces induced by the RBC membrane-cytoskeleton composite has not yet been fully understood. In this study, we use a theoretical model for lipid bilayer mechanics, cytoskeleton deformation, and membrane-merozoite interactions to systematically investigate the influence of effective RBC membrane tension, which includes contributions from the lipid bilayer tension, spontaneous tension, interfacial tension, and the resistance of cytoskeleton against shear deformation on the progression of membrane wrapping during the process of malaria invasion. Our model reveals that this effective membrane tension creates a wrapping energy barrier for a complete merozoite entry. We calculate the tension threshold required to impede the malaria invasion. We find that the tension threshold is a nonmonotonic function of spontaneous tension and undergoes a sharp transition from large to small values as the magnitude of interfacial tension increases. We also predict that the physical properties of the RBC cytoskeleton layer-particularly the resting length of the cytoskeleton-play key roles in specifying the degree of the membrane wrapping. We also found that the shear energy of cytoskeleton deformation diverges at the full wrapping state, suggesting the local disassembly of the cytoskeleton is required to complete the merozoite entry. Additionally, using our theoretical framework, we predict the landscape of myosin-mediated forces and the physical properties of the RBC membrane in regulating successful malaria invasion. Our findings on the crucial role of RBC membrane tension in inhibiting malaria invasion can have implications for developing novel antimalarial therapeutic or vaccine-based strategies.
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Affiliation(s)
- Haleh Alimohamadi
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, United States of America
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California, United States of America
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Hou M, Xing F, Yang J, Hu F, Pan L, Xu J. Molecular Resolution Mapping of Erythrocyte Cytoskeleton by Ultrastructure Expansion Single-Molecule Localization Microscopy. SMALL METHODS 2023; 7:e2201243. [PMID: 36543363 DOI: 10.1002/smtd.202201243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/26/2022] [Indexed: 06/17/2023]
Abstract
The combination of expansion microscopy and single-molecule localization microscopy has the potential to approach the molecular resolution. However, this combination meets challenges due to the hydrogel shrinkage in the presence of imaging buffer. Here, a method of ultrastructure expansion single-molecule localization microscopy (U-ExSMLM) based on skillfully adhering the gel onto poly-l-lysine (pLL)-coated coverslip is developed to prevent lateral shrinkage of the hydrogel. U-ExSMLM is then applied to dissect the membrane cytoskeleton organization of human erythrocytes at molecular resolution. The resolved nanoscale spatial distributions of cytoskeleton proteins, including the N/C-termini of β-spectrin, protein 4.1, and tropomodulin, show good agreement with the acknowledged model of erythrocyte cytoskeleton structure, demonstrating the reliability of U-ExSMLM. Furthermore, the concentration of pLL is adjusted to preserve the physiological biconcave morphology of erythrocytes, and it is found that the spectrin cytoskeleton in the dimple regions has lower density and larger length than that in the rim regions, which provides the direct evidence for cytoskeleton asymmetry in human erythrocytes. Therefore, the integrated method offers future opportunities to study the ultrastructure of membrane cytoskeleton at molecular resolution.
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Affiliation(s)
- Mengdi Hou
- The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry, School of Physics and TEDA Institute of Applied Physics, Nankai University, Tianjin, 300071, China
| | - Fulin Xing
- The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry, School of Physics and TEDA Institute of Applied Physics, Nankai University, Tianjin, 300071, China
| | - Jianyu Yang
- The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry, School of Physics and TEDA Institute of Applied Physics, Nankai University, Tianjin, 300071, China
| | - Fen Hu
- The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry, School of Physics and TEDA Institute of Applied Physics, Nankai University, Tianjin, 300071, China
| | - Leiting Pan
- The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry, School of Physics and TEDA Institute of Applied Physics, Nankai University, Tianjin, 300071, China
- State Key Laboratory of Medicinal Chemical Biology, Frontiers Science Center for Cell Responses, College of Life Sciences, Nankai University, Tianjin, 300071, China
- Shenzhen Research Institute of Nankai University, Shenzhen, Guangdong, 518083, China
| | - Jingjun Xu
- The Key Laboratory of Weak-Light Nonlinear Photonics of Education Ministry, School of Physics and TEDA Institute of Applied Physics, Nankai University, Tianjin, 300071, China
- Shenzhen Research Institute of Nankai University, Shenzhen, Guangdong, 518083, China
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Ghisleni A, Bonilla-Quintana M, Crestani M, Fukuzawa A, Rangamani P, Gauthier N. Mechanically induced topological transition of spectrin regulates its distribution in the mammalian cortex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.02.522381. [PMID: 36712133 PMCID: PMC9881866 DOI: 10.1101/2023.01.02.522381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The cell cortex is a dynamic assembly that ensures cell integrity during passive deformation or active response by adapting cytoskeleton topologies with poorly understood mechanisms. The spectrin meshwork ensures such adaptation in erythrocytes and neurons. Erythrocytes rely on triangular-like lattices of spectrin tetramers, which in neurons are organized in periodic arrays. We exploited Expansion Microscopy to discover that these two distinct topologies can co-exist in other mammalian cells such as fibroblasts. We show through biophysical measurements and computational modeling that spectrin provides coverage of the cortex and, with the intervention of actomyosin, erythroid-like lattices can dynamically transition into condensates resembling neuron-like periodic arrays fenced by actin stress fibers. Spectrin condensates experience lower mechanical stress and turnover despite displaying an extension close to the contour length of the tetramer. Our study sheds light on the adaptive properties of spectrin, which ensures protection of the cortex by undergoing mechanically induced topological transitions.
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Rezghi A, Zhang J. Tank-treading dynamics of red blood cells in shear flow: On the membrane viscosity rheology. Biophys J 2022; 121:3393-3410. [PMID: 35986517 PMCID: PMC9515232 DOI: 10.1016/j.bpj.2022.08.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/12/2022] [Accepted: 08/15/2022] [Indexed: 11/28/2022] Open
Abstract
In this article, extensive three-dimensional simulations are conducted for tank-treading (TT) red blood cells (RBCs) in shear flow with different cell viscous properties and flow conditions. Apart from recent numerical studies on TT RBCs, this research considers the uncertainty in cytoplasm viscosity, covers a more complete range of shear flow situations of available experiments, and examines the TT behaviors in more details. Key TT characteristics, including the rotation frequency, deformation index, and inclination angle, are compared with available experimental results of similar shear flow conditions. Fairly good simulation-experiment agreements for these parameters can be obtained by adjusting the membrane viscosity values; however, different rheological relationships between the membrane viscosity and the flow shear rate are noted for these comparisons: shear thinning from the TT frequency, Newtonian from the inclination angle, and shear thickening from the cell deformation. Previous studies claimed a shear-thinning membrane viscosity model based on the TT frequency results; however, such a conclusion seems premature from our results and more carefully designed and better controlled investigations are required for the RBC membrane rheology. In addition, our simulation results reveal complicate RBC TT features and such information could be helpful for a better understanding of in vivo and in vitro RBC dynamics.
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Affiliation(s)
- Ali Rezghi
- Bharti School of Engineering and Computer Science, Laurentian University, Sudbury, Ontario, Canada
| | - Junfeng Zhang
- Bharti School of Engineering and Computer Science, Laurentian University, Sudbury, Ontario, Canada.
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Leterrier C, Pullarkat PA. Mechanical role of the submembrane spectrin scaffold in red blood cells and neurons. J Cell Sci 2022; 135:276327. [PMID: 35972759 DOI: 10.1242/jcs.259356] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Spectrins are large, evolutionarily well-conserved proteins that form highly organized scaffolds on the inner surface of eukaryotic cells. Their organization in different cell types or cellular compartments helps cells withstand mechanical challenges with unique strategies depending on the cell type. This Review discusses our understanding of the mechanical properties of spectrins, their very distinct organization in red blood cells and neurons as two examples, and the contribution of the scaffolds they form to the mechanical properties of these cells.
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Affiliation(s)
- Christophe Leterrier
- Aix Marseille Université, CNRS, INP UMR 7051, NeuroCyto, Marseille 13005, France
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Garcia‐Herreros A, Yeh Y, Peng Z, del Álamo JC. Cyclic Mechanical Stresses Alter Erythrocyte Membrane Composition and Microstructure and Trigger Macrophage Phagocytosis. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2201481. [PMID: 35508805 PMCID: PMC9284186 DOI: 10.1002/advs.202201481] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Indexed: 06/01/2023]
Abstract
Red blood cells (RBCs) are cleared from the circulation when they become damaged or display aging signals targeted by macrophages. This process occurs mainly in the spleen, where blood flows through submicrometric constrictions called inter-endothelial slits (IES), subjecting RBCs to large-amplitude deformations. In this work, RBCs are circulated through microfluidic devices containing microchannels that replicate the IES. The cyclic mechanical stresses experienced by the cells affect their biophysical properties and molecular composition, accelerating cell aging. Specifically, RBCs quickly transition to a more spherical, less deformable phenotype that hinders microchannel passage, causing hemolysis. This transition is associated with the release of membrane vesicles, which self-extinguishes as the spacing between membrane-cytoskeleton linkers becomes tighter. Proteomics analysis of the mechanically aged RBCs reveals significant losses of essential proteins involved in antioxidant protection, gas transport, and cell metabolism. Finally, it is shown that these changes make mechanically aged RBCs more susceptible to macrophage phagocytosis. These results provide a comprehensive model explaining how physical stress induces RBC clearance in the spleen. The data also suggest new biomarkers of early "hemodamage" and inflammation preceding hemolysis in RBCs subjected to mechanical stress.
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Affiliation(s)
- Antoni Garcia‐Herreros
- Department of Mechanical and Aerospace EngineeringUniversity of California9500 Gilman Dr.La JollaCA92093USA
| | - Yi‐Ting Yeh
- Department of Mechanical and Aerospace EngineeringUniversity of California9500 Gilman Dr.La JollaCA92093USA
- Department of BioengineeringUniversity of California9500 Gilman Dr.La JollaCA92093USA
- Institute of Engineering in MedicineUniversity of California9500 Gilman Dr.La JollaCA92093USA
| | - Zhangli Peng
- Department of BioengineeringUniversity of Illinois at Chicago1200 W Harrison StChicagoIL60607USA
| | - Juan C. del Álamo
- Department of Mechanical and Aerospace EngineeringUniversity of California9500 Gilman Dr.La JollaCA92093USA
- Institute of Engineering in MedicineUniversity of California9500 Gilman Dr.La JollaCA92093USA
- Department of Mechanical EngineeringUniversity of Washington850 Republican StSeattleWA98109USA
- Center for Cardiovascular BiologyUniversity of Washington850 Republican StSeattleWA98109USA
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Jäger J, Patra P, Sanchez CP, Lanzer M, Schwarz US. A particle-based computational model to analyse remodelling of the red blood cell cytoskeleton during malaria infections. PLoS Comput Biol 2022; 18:e1009509. [PMID: 35394995 PMCID: PMC9020725 DOI: 10.1371/journal.pcbi.1009509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 04/20/2022] [Accepted: 03/21/2022] [Indexed: 11/18/2022] Open
Abstract
Red blood cells can withstand the harsh mechanical conditions in the vasculature only because the bending rigidity of their plasma membrane is complemented by the shear elasticity of the underlying spectrin-actin network. During an infection by the malaria parasite Plasmodium falciparum, the parasite mines host actin from the junctional complexes and establishes a system of adhesive knobs, whose main structural component is the knob-associated histidine rich protein (KAHRP) secreted by the parasite. Here we aim at a mechanistic understanding of this dramatic transformation process. We have developed a particle-based computational model for the cytoskeleton of red blood cells and simulated it with Brownian dynamics to predict the mechanical changes resulting from actin mining and KAHRP-clustering. Our simulations include the three-dimensional conformations of the semi-flexible spectrin chains, the capping of the actin protofilaments and several established binding sites for KAHRP. For the healthy red blood cell, we find that incorporation of actin protofilaments leads to two regimes in the shear response. Actin mining decreases the shear modulus, but knob formation increases it. We show that dynamical changes in KAHRP binding affinities can explain the experimentally observed relocalization of KAHRP from ankyrin to actin complexes and demonstrate good qualitative agreement with experiments by measuring pair cross-correlations both in the computer simulations and in super-resolution imaging experiments. Malaria is one of the deadliest infectious diseases and its symptoms are related to the blood stage, when the parasite multiplies within red blood cells. In order to avoid clearance by the spleen, the parasite produces specific factors like the adhesion receptor PfEMP1 and the multifunctional protein KAHRP that lead to the formation of adhesive knobs on the surface of the red blood cells and thus increase residence time in the vasculature. We have developed a computational model for the parasite-induced remodelling of the actin-spectrin network to quantitatively predict the dynamical changes in the mechanical properties of the infected red blood cells and the spatial distribution of the different protein components of the membrane skeleton. Our simulations show that KAHRP can relocate to actin junctions due to dynamical changes in binding affinities, in good qualitative agreement with super-resolution imaging experiments. In the future, our simulation framework can be used to gain further mechanistic insight into the way malaria parasites attack the red blood cell cytoskeleton.
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Affiliation(s)
- Julia Jäger
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
| | - Pintu Patra
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
| | - Cecilia P. Sanchez
- Center of Infectious Diseases, Parasitology, University Hospital Heidelberg, Heidelberg, Germany
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, University Hospital Heidelberg, Heidelberg, Germany
- * E-mail: (ML); (USS)
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics, Heidelberg University, Heidelberg, Germany
- BioQuant-Center for Quantitative Biology, Heidelberg University, Heidelberg, Germany
- * E-mail: (ML); (USS)
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