1
|
Chouhan G, Lewis NS, Ghanekar V, Koti Ainavarapu SR, Inamdar MM, Sonawane M. Cell-size-dependent regulation of Ezrin dictates epithelial resilience to stretch by countering myosin-II-mediated contractility. Cell Rep 2024; 43:114271. [PMID: 38823013 DOI: 10.1016/j.celrep.2024.114271] [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: 06/29/2023] [Revised: 04/22/2024] [Accepted: 05/09/2024] [Indexed: 06/03/2024] Open
Abstract
The epithelial adaptations to mechanical stress are facilitated by molecular and tissue-scale changes that include the strengthening of junctions, cytoskeletal reorganization, and cell-proliferation-mediated changes in tissue rheology. However, the role of cell size in controlling these properties remains underexplored. Our experiments in the zebrafish embryonic epidermis, guided by theoretical estimations, reveal a link between epithelial mechanics and cell size, demonstrating that an increase in cell size compromises the tissue fracture strength and compliance. We show that an increase in E-cadherin levels in the proliferation-deficient epidermis restores epidermal compliance but not the fracture strength, which is largely regulated by Ezrin-an apical membrane-cytoskeleton crosslinker. We show that Ezrin fortifies the epithelium in a cell-size-dependent manner by countering non-muscle myosin-II-mediated contractility. This work uncovers the importance of cell size maintenance in regulating the mechanical properties of the epithelium and fostering protection against future mechanical stresses.
Collapse
Affiliation(s)
- Geetika Chouhan
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Natasha Steffi Lewis
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | - Vallari Ghanekar
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India
| | | | - Mandar M Inamdar
- Department of Civil Engineering, Indian Institute of Technology Bombay, Mumbai, India.
| | - Mahendra Sonawane
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai, India.
| |
Collapse
|
2
|
Yadegari F, Gabler Pizarro LA, Marquez-Curtis LA, Elliott JAW. Temperature Dependence of Membrane Permeability Parameters for Five Cell Types Using Nonideal Thermodynamic Assumptions to Mathematically Model Cryopreservation Protocols. J Phys Chem B 2024; 128:1139-1160. [PMID: 38291962 PMCID: PMC10860702 DOI: 10.1021/acs.jpcb.3c04534] [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: 07/05/2023] [Revised: 10/15/2023] [Accepted: 11/17/2023] [Indexed: 02/01/2024]
Abstract
Cryopreservation is the process of preserving biological matter at subzero temperatures for long-term storage. During cryopreservation, cells are susceptible to various injuries that can be mitigated by controlling the cooling and warming profiles and cryoprotective agent (CPA) addition and removal procedures. Mathematical modeling of the changing cell volume at different temperatures can greatly reduce the experiments needed to optimize cryopreservation protocols. Such mathematical modeling requires as inputs the cell membrane permeabilities to water and CPA and the osmotically inactive fraction of the cell. Since the intra- and extracellular solutions are generally thermodynamically nonideal, our group has been incorporating the osmotic virial equation to model the solution thermodynamics that underlie the cell volume change equations, adding the second and third osmotic virial coefficients of the grouped intracellular solute to the cell osmotic parameters that must be measured. In our previous work, we reported methods to obtain cell osmotic parameters at room temperature by fitting experimental cell volume kinetic data with equations that incorporated nonideal solution thermodynamics assumptions. Since the relevant cell volume excursions occur at different temperatures, the temperature dependence of the osmotic parameters plays an important role. In this work, we present a new two-part fitting method to obtain five cell-type-specific parameters (water permeability, dimethyl sulfoxide permeability, osmotically inactive fraction, and the second and third osmotic virial coefficients of the intracellular solution) from experimental measurements of equilibrium cell volume and cell volume as a function of time at room temperature and 0 °C for five cell types, namely, human umbilical vein endothelial cells (HUVECs), H9c2 rat myoblasts, porcine corneal endothelial cells (PCECs), the Jurkat T-lymphocyte cell line, and human cerebral microvascular endothelial cells (hCMECs/D3 cell line). The fitting method in this work is based on both equilibrium and kinetic cell volume data, enabling us to solve some technical challenges and expand our previously reported measurement technique to 0 °C. Finally, we use the measured parameters to model the cell volume changes for a HUVEC cryopreservation protocol to demonstrate the impact of the nonideal thermodynamic assumptions on predicting the changing cell volume during freezing and thawing.
Collapse
Affiliation(s)
- Faranak Yadegari
- Department
of Chemical and Materials Engineering, University
of Alberta, Edmonton, AB, T6G 1H9, Canada
- Department
of Laboratory Medicine and Pathology, University
of Alberta, Edmonton, AB, T6G 1C9, Canada
| | - Laura A. Gabler Pizarro
- Department
of Chemical and Materials Engineering, University
of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Leah A. Marquez-Curtis
- Department
of Chemical and Materials Engineering, University
of Alberta, Edmonton, AB, T6G 1H9, Canada
- Department
of Laboratory Medicine and Pathology, University
of Alberta, Edmonton, AB, T6G 1C9, Canada
| | - Janet A. W. Elliott
- Department
of Chemical and Materials Engineering, University
of Alberta, Edmonton, AB, T6G 1H9, Canada
- Department
of Laboratory Medicine and Pathology, University
of Alberta, Edmonton, AB, T6G 1C9, Canada
| |
Collapse
|
3
|
Yoshikawa K, Saito S, Kadonosono T, Tanaka M, Okochi M. Osmotic stress induces the formation of migrasome-like vesicles. FEBS Lett 2024; 598:437-445. [PMID: 38339800 DOI: 10.1002/1873-3468.14816] [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: 12/05/2023] [Revised: 01/10/2024] [Accepted: 01/10/2024] [Indexed: 02/12/2024]
Abstract
Migrasomes are extracellular vesicles that form on the retraction fibers of migrating cells. In this study, we report the formation of migrasome-like vesicles enriched in tetraspanin 4 and containing cytoplasmic components in response to hypoosmotic stress. When migrating cells were subjected to hypoosmotic stress, vesicles with a size distribution of 0.5 to 2 μm formed on the retraction fibers, and vanished in a few minutes. The vesicles are rich in cholesterol, and their number was reduced when cells were pretreated with lipoprotein-deficient serum. The formation of migrasome-like vesicles upon hypoosmotic stress may provide biophysical cues regarding the cellular response to this external stimulus in cells and tissues.
Collapse
Grants
- 23K17843 Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan
- 22K19913 Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan
- 21H01726 Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan
- 21H01725 Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science, and Technology of Japan
- JP21zf0127004 Moonshot Research and Development Program from the Japan Agency for Medical Research and Development (AMED)
Collapse
Affiliation(s)
- Koki Yoshikawa
- Department of Chemical Science and Engineering, Tokyo Institute of Technology, Japan
| | - Shogo Saito
- Department of Chemical Science and Engineering, Tokyo Institute of Technology, Japan
| | - Tetsuya Kadonosono
- Department of Life Science and Technology, Tokyo Institute of Technology, Yokohama-shi, Japan
| | - Masayoshi Tanaka
- Department of Chemical Science and Engineering, Tokyo Institute of Technology, Yokohama-shi, Japan
| | - Mina Okochi
- Department of Chemical Science and Engineering, Tokyo Institute of Technology, Japan
| |
Collapse
|
4
|
Claude-Taupin A, Dupont N. To squeeze or not: Regulation of cell size by mechanical forces in development and human diseases. Biol Cell 2024; 116:e2200101. [PMID: 38059665 DOI: 10.1111/boc.202200101] [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: 10/26/2022] [Revised: 11/27/2023] [Accepted: 11/29/2023] [Indexed: 12/08/2023]
Abstract
Physical constraints, such as compression, shear stress, stretching and tension play major roles during development and tissue homeostasis. Mechanics directly impact physiology, and their alteration is also recognized as having an active role in driving human diseases. Recently, growing evidence has accumulated on how mechanical forces are translated into a wide panel of biological responses, including metabolism and changes in cell morphology. The aim of this review is to summarize and discuss our knowledge on the impact of mechanical forces on cell size regulation. Other biological consequences of mechanical forces will not be covered by this review. Moreover, wherever possible, we also discuss mechanosensors and molecular and cellular signaling pathways upstream of cell size regulation. We finally highlight the relevance of mechanical forces acting on cell size in physiology and human diseases.
Collapse
Affiliation(s)
- Aurore Claude-Taupin
- Institut Necker Enfants Malades (INEM), INSERM UMR-S1151, CNRS UMR-S8253, Université Paris Cité, Paris, France
| | - Nicolas Dupont
- Institut Necker Enfants Malades (INEM), INSERM UMR-S1151, CNRS UMR-S8253, Université Paris Cité, Paris, France
| |
Collapse
|
5
|
Tokamov SA, Buiter S, Ullyot A, Scepanovic G, Williams AM, Fernandez-Gonzalez R, Horne-Badovinac S, Fehon RG. Cortical tension promotes Kibra degradation via Par-1. Mol Biol Cell 2024; 35:ar2. [PMID: 37903240 PMCID: PMC10881160 DOI: 10.1091/mbc.e23-06-0246] [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: 06/26/2023] [Revised: 10/17/2023] [Accepted: 10/20/2023] [Indexed: 11/01/2023] Open
Abstract
The Hippo pathway is an evolutionarily conserved regulator of tissue growth. Multiple Hippo signaling components are regulated via proteolytic degradation. However, how these degradation mechanisms are themselves modulated remains unexplored. Kibra is a key upstream pathway activator that promotes its own ubiquitin-mediated degradation upon assembling a Hippo signaling complex. Here, we demonstrate that Hippo complex-dependent Kibra degradation is modulated by cortical tension. Using classical genetic, osmotic, and pharmacological manipulations of myosin activity and cortical tension, we show that increasing cortical tension leads to Kibra degradation, whereas decreasing cortical tension increases Kibra abundance. Our study also implicates Par-1 in regulating Kib abundance downstream of cortical tension. We demonstrate that Par-1 promotes ubiquitin-mediated Kib degradation in a Hippo complex-dependent manner and is required for tension-induced Kib degradation. Collectively, our results reveal a previously unknown molecular mechanism by which cortical tension affects Hippo signaling and provide novel insights into the role of mechanical forces in growth control.
Collapse
Affiliation(s)
- Sherzod A. Tokamov
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Stephan Buiter
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Anne Ullyot
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Gordana Scepanovic
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Rodrigo Fernandez-Gonzalez
- Institute of Biomedical Engineering and Department of Cell and Systems Biology, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| | - Richard G. Fehon
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637
| |
Collapse
|
6
|
Efremov YM, Shimolina L, Gulin A, Ignatova N, Gubina M, Kuimova MK, Timashev PS, Shirmanova MV. Correlation of Plasma Membrane Microviscosity and Cell Stiffness Revealed via Fluorescence-Lifetime Imaging and Atomic Force Microscopy. Cells 2023; 12:2583. [PMID: 37947661 PMCID: PMC10650173 DOI: 10.3390/cells12212583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 10/23/2023] [Accepted: 10/31/2023] [Indexed: 11/12/2023] Open
Abstract
The biophysical properties of cells described at the level of whole cells or their membranes have many consequences for their biological behavior. However, our understanding of the relationships between mechanical parameters at the level of cell (stiffness, viscoelasticity) and at the level of the plasma membrane (fluidity) remains quite limited, especially in the context of pathologies, such as cancer. Here, we investigated the correlations between cells' stiffness and viscoelastic parameters, mainly determined via the actin cortex, and plasma membrane microviscosity, mainly determined via its lipid profile, in cancer cells, as these are the keys to their migratory capacity. The mechanical properties of cells were assessed using atomic force microscopy (AFM). The microviscosity of membranes was visualized using fluorescence-lifetime imaging microscopy (FLIM) with the viscosity-sensitive probe BODIPY 2. Measurements were performed for five human colorectal cancer cell lines that have different migratory activity (HT29, Caco-2, HCT116, SW 837, and SW 480) and their chemoresistant counterparts. The actin cytoskeleton and the membrane lipid composition were also analyzed to verify the results. The cell stiffness (Young's modulus), measured via AFM, correlated well (Pearson r = 0.93) with membrane microviscosity, measured via FLIM, and both metrics were elevated in more motile cells. The associations between stiffness and microviscosity were preserved upon acquisition of chemoresistance to one of two chemotherapeutic drugs. These data clearly indicate that mechanical parameters, determined by two different cellular structures, are interconnected in cells and play a role in their intrinsic migratory potential.
Collapse
Affiliation(s)
- Yuri M. Efremov
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia;
| | - Liubov Shimolina
- Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 603005 Nizhny Novgorod, Russia; (L.S.); (N.I.); (M.V.S.)
| | - Alexander Gulin
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia; (A.G.); (M.G.)
| | - Nadezhda Ignatova
- Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 603005 Nizhny Novgorod, Russia; (L.S.); (N.I.); (M.V.S.)
| | - Margarita Gubina
- N.N. Semenov Federal Research Center for Chemical Physics, Russian Academy of Sciences, 119991 Moscow, Russia; (A.G.); (M.G.)
| | - Marina K. Kuimova
- Department of Chemistry, Imperial College London, White City Campus, London W12 0BZ, UK;
| | - Peter S. Timashev
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), 119991 Moscow, Russia;
- World-Class Research Center “Digital Biodesign and Personalized Healthcare”, Sechenov University, 119991 Moscow, Russia
| | - Marina V. Shirmanova
- Institute of Experimental Oncology and Biomedical Technologies, Privolzhsky Research Medical University, 603005 Nizhny Novgorod, Russia; (L.S.); (N.I.); (M.V.S.)
| |
Collapse
|
7
|
Höllring K, Vurnek D, Gehrer S, Dudziak D, Hubert M, Smith AS. Morphology as indicator of adaptive changes of model tissues in osmotically and chemically changing environments. BIOMATERIALS ADVANCES 2023; 154:213635. [PMID: 37804683 DOI: 10.1016/j.bioadv.2023.213635] [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: 01/16/2023] [Revised: 08/23/2023] [Accepted: 09/19/2023] [Indexed: 10/09/2023]
Abstract
We investigate the formation and maintenance of the homeostatic state in the case of 2D epithelial tissues following an induction of hyperosmotic conditions, using media enriched with 80 to 320 mOsm of mannitol, NaCl, and urea. We characterise the changes in the tissue immediately after the osmotic shock, and follow it until the new homeostatic state is formed. We characterise changes in cooperative motility and proliferation pressure in the tissue upon treatment with the help of a theoretical model based on the delayed Fisher-Kolmogorov formalism, where the delay in density evolution is induced by the the finite time of the cell division. Finally we explore the adaptation of the homeostatic tissue to highly elevated osmotic conditions by evaluating the morphology and topology of cells after 20 days in incubation. We find that hyperosmotic environments together with changes in the extracellular matrix induce different mechanical states in viable tissues, where only some remain functional. The perspective is a relation between tissue topology and function, which could be explored beyond the scope of this manuscript. Experimental investigation of morphological effect of change of osmotic conditions on long-term tissue morphology and topology Effect of osmotic changes on transient tissue growth behaviour Analysis of recovery process of tissues post-osmotic-shock Toxicity limits of osmolytes in mid- to long-term tissue evolution Tissue adaptation to physiological changes in environment Long-term tissue stabilisation under altered osmotic conditions.
Collapse
Affiliation(s)
- Kevin Höllring
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany
| | - Damir Vurnek
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany; Laboratory of Dendritic Cell Biology, Department of Dermatology, FAU Erlangen-Nürnberg, University Hospital Erlangen, Erlangen 91052, Germany
| | - Simone Gehrer
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany
| | - Diana Dudziak
- Laboratory of Dendritic Cell Biology, Department of Dermatology, FAU Erlangen-Nürnberg, University Hospital Erlangen, Erlangen 91052, Germany
| | - Maxime Hubert
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany; Group of Computational Life Sciences, Department of Physical Chemistry, Ruer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia
| | - Ana-Sunčana Smith
- PULS Group, Institute for Theoretical Physics, FAU Erlangen-Nürnberg, Cauerstraße 3, 91058 Erlangen, Germany; Group of Computational Life Sciences, Department of Physical Chemistry, Ruer Bošković Institute, Bijenička 54, Zagreb 10000, Croatia.
| |
Collapse
|
8
|
Tokamov SA, Nouri N, Rich A, Buiter S, Glotzer M, Fehon RG. Apical polarity and actomyosin dynamics control Kibra subcellular localization and function in Drosophila Hippo signaling. Dev Cell 2023; 58:1864-1879.e4. [PMID: 37729921 PMCID: PMC10591919 DOI: 10.1016/j.devcel.2023.08.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/02/2023] [Accepted: 08/24/2023] [Indexed: 09/22/2023]
Abstract
The Hippo pathway is an evolutionarily conserved regulator of tissue growth that integrates inputs from both polarity and actomyosin networks. An upstream activator of the Hippo pathway, Kibra, localizes at the junctional and medial regions of the apical cortex in epithelial cells, and medial accumulation promotes Kibra activity. Here, we demonstrate that cortical Kibra distribution is controlled by a tug-of-war between apical polarity and actomyosin dynamics. We show that while the apical polarity network, in part via atypical protein kinase C (aPKC), tethers Kibra at the junctional cortex to silence its activity, medial actomyosin flows promote Kibra-mediated Hippo complex formation at the medial cortex, thereby activating the Hippo pathway. This study provides a mechanistic understanding of the relationship between the Hippo pathway, polarity, and actomyosin cytoskeleton, and it offers novel insights into how fundamental features of epithelial tissue architecture can serve as inputs into signaling cascades that control tissue growth, patterning, and morphogenesis.
Collapse
Affiliation(s)
- Sherzod A Tokamov
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA; Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Nicki Nouri
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Ashley Rich
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Stephan Buiter
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Michael Glotzer
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA
| | - Richard G Fehon
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL 60637, USA; Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, IL 60637, USA.
| |
Collapse
|
9
|
Su R, Wang S, McDargh Z, O'Shaughnessy B. Three membrane fusion pore families determine the pathway to pore dilation. Biophys J 2023; 122:3986-3998. [PMID: 37644721 PMCID: PMC10560699 DOI: 10.1016/j.bpj.2023.08.021] [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: 12/20/2022] [Revised: 06/19/2023] [Accepted: 08/25/2023] [Indexed: 08/31/2023] Open
Abstract
During exocytosis secretory vesicles fuse with a target membrane and release neurotransmitters, hormones, or other bioactive molecules through a membrane fusion pore. The initially small pore may subsequently dilate for full contents release, as commonly observed in amperometric traces. The size, shape, and evolution of the pore is critical to the course of contents release, but exact fusion pore solutions accounting for membrane tension and bending energy constraints have not been available. Here, we obtained exact solutions for fusion pores between two membranes. We find three families: a narrow pore, a wide pore, and an intermediate tether-like pore. For high tensions these are close to the catenoidal and tether solutions recently reported for freely hinged membrane boundaries. We suggest membrane fusion initially generates a stable narrow pore, and the dilation pathway is a transition to the stable wide pore family. The unstable intermediate pore is the transition state that sets the energy barrier for this dilation pathway. Pore dilation is mechanosensitive, as the energy barrier is lowered by increased membrane tension. Finally, we study fusion pores in nanodiscs, powerful systems for the study of individual pores. We show that nanodiscs stabilize fusion pores by locking them into the narrow pore family.
Collapse
Affiliation(s)
- Rui Su
- Department of Chemical Engineering, Columbia University, New York City, New York
| | - Shuyuan Wang
- Department of Chemical Engineering, Columbia University, New York City, New York; Department of Physics, Columbia University, New York City, New York
| | - Zachary McDargh
- Department of Chemical Engineering, Columbia University, New York City, New York
| | - Ben O'Shaughnessy
- Department of Chemical Engineering, Columbia University, New York City, New York.
| |
Collapse
|
10
|
Azam I, Benson JD. Silymarin mediated osmotic responses and damage in HepG2 cell suspensions and monolayers. Cryobiology 2023; 112:104552. [PMID: 37301358 DOI: 10.1016/j.cryobiol.2023.104552] [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: 04/18/2023] [Revised: 05/19/2023] [Accepted: 06/07/2023] [Indexed: 06/12/2023]
Abstract
Maintenance of cells within a volume range compatible with their functional integrity is a critical determinant of cell survival after cryopreservation, and quantifying this osmotically induced damage is a part of the rational design of improved cryopreservation protocols. The degree that cells tolerate osmotic stress significantly impacts applicable cryoprotocols, but there has been little research on the time dependence of this osmotic stress. Additionally, the flavonoid silymarin has been shown to be hepatoprotective. Therefore, here we test the hypotheses that osmotic damage is time-dependent and that flavonoid inclusion reduces osmotic damage. In our first experiment, cells were exposed to a series of anisosmotic solutions of graded hypo- and hypertonicity for 10-40 min, resulting in a conclusion that osmotically induced damage is time dependent. In the next experiment, adherent cells preincubated with silymarin at the concentration of 10-4 mol/L and 10-5 mol/L showed a significant increase in cell proliferation and metabolic activity after osmotic stress compared to untreated matched controls. For instance, when adherent cells preincubated with 10-5 mol/L silymarin were tested, resistance to osmotic damage and a significant increase (15%) in membrane integrity was observed in hypo-osmotic media and a 22% increase in hyperosmotic conditions. Similarly, significant protection from osmotic damage was observed in suspended HepG2 cells in the presence of silymarin. Our study concludes that osmotic damage is time dependent, and the addition of silymarin leads to elevated resistance to osmotic stress and a potential increase in the cryosurvival of HepG2 cells.
Collapse
Affiliation(s)
- Iqra Azam
- Department of Biology, University of Saskatchewan, Canada
| | - James D Benson
- Department of Biology, University of Saskatchewan, Canada.
| |
Collapse
|
11
|
Miyano T, Suzuki A, Sakamoto N. Actin cytoskeletal reorganization is involved in hyperosmotic stress-induced autophagy in tubular epithelial cells. Biochem Biophys Res Commun 2023; 663:1-7. [PMID: 37116392 DOI: 10.1016/j.bbrc.2023.04.070] [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: 04/06/2023] [Revised: 04/14/2023] [Accepted: 04/20/2023] [Indexed: 04/30/2023]
Abstract
Tubular epithelial cells are routinely exposed to severe changes in osmolarity. Although the autophagic activity of cells is an indispensable process to maintain cellular homeostasis and respond to stressors, the effect of hyperosmotic stress on autophagic activity in tubular epithelial cells remains unknown. The aim of this study was to determine the effect of hyperosmotic stress on autophagy in rat kidney tubular epithelial cells focusing on the role of actin and microtubule cytoskeletons. Normal rat kidney (NRK)-52E cells exposed to mannitol-induced hyperosmotic stress. As a result, NRK-52E cells showed elevated protein levels of the autophagosome marker LC3-II, indicating enhancement of the autophagic flux. Hyperosmotic stress also transiently decreased cell volume and caused the reorganization of actin and microtubule cytoskeletal structures in NRK-52E cells. The inhibition of the actin cytoskeleton reorganization by cytochalasin D impaired the increase in the levels of LC3-II; however, disassembly of the microtubules following treatment with nocodazole did not affect the increase. These results indicate that hyperosmotic stress can induce autophagy mediated by the reorganization of the actin cytoskeleton in tubular epithelial cells.
Collapse
Affiliation(s)
- Takashi Miyano
- Department of Mechanical Systems Engineering, Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan.
| | - Atsushi Suzuki
- Department of Mechanical Systems Engineering, Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan
| | - Naoya Sakamoto
- Department of Mechanical Systems Engineering, Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan.
| |
Collapse
|
12
|
Understanding the Combined Effects of High Glucose Induced Hyper-Osmotic Stress and Oxygen Tension in the Progression of Tumourigenesis: From Mechanism to Anti-Cancer Therapeutics. Cells 2023; 12:cells12060825. [PMID: 36980166 PMCID: PMC10047272 DOI: 10.3390/cells12060825] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/03/2023] [Accepted: 02/17/2023] [Indexed: 03/09/2023] Open
Abstract
High glucose (HG), a hallmark of the tumour microenvironment, is also a biomechanical stressor, as it exerts hyper-osmotic stress (HG-HO), but not much is known regarding how tumour cells mechanoadapt to HG-HO. Therefore, this study aimed to delineate the novel molecular mechanisms by which tumour cells mechanoadapt to HG/HG-HO and whether phytochemical-based interference in these mechanisms can generate tumour-cell-selective vulnerability to cell death. Mannitol and L-glucose were used as hyper-osmotic equivalents of high glucose. The results revealed that the tumour cells can efficiently mechanoadapt to HG-HO only in the normoxic microenvironment. Under normoxic HG/HG-HO stress, tumour cells polySUMOylate a higher pool of mitotic driver pH3(Ser10), which translocates to the nucleus and promotes faster cell divisions. On the contrary, acute hypoxia dampens HG/HG-HO-associated excessive proliferation by upregulating sentrin protease SENP7. SENP7 promotes abnormal SUMOylation of pH3(Ser10), thereby restricting its nuclear entry and promoting the M-phase arrest and cell loss. However, the hypoxia-arrested cells that managed to survive showed relapse upon reversal to normoxia as well as upregulation of pro-survival-associated SENP1, and players in tumour growth signalling, autophagy, glycolytic pathways etc. Depletion of SENP1 in both normoxia and hypoxia caused significant loss of tumour cells vs undepleted controls. SENP1 was ascertained to restrict the abnormal SUMOylation of pH3(Ser10) in both normoxia and hypoxia, although not so efficiently in hypoxia, due to the opposing activity of SENP7. Co-treatment with Momordin Ic (MC), a natural SENP1 inhibitor, and Gallic Acid (GA), an inhibitor of identified major pro-tumourigenic signalling (both enriched in Momordica charantia), eliminated surviving tumour cells in normal glucose, HG and HG-HO normoxic and hypoxic microenvironments, suggesting that appropriate and enhanced polySUMOylation of pH3(Ser10) in response to HG/HG-HO stress was attenuated by this treatment along with further dampening of other key tumourigenic signalling, due to which tumour cells could no longer proliferate and grow.
Collapse
|
13
|
Zhen YY, Wu CH, Chen HC, Chang EE, Lee JJ, Chen WY, Chang JM, Tseng PY, Wang YF, Hung CC. Coordination of LMO7 with FAK Signaling Sustains Epithelial Integrity in Renal Epithelia Exposed to Osmotic Pressure. Cells 2022; 11:cells11233805. [PMID: 36497072 PMCID: PMC9741450 DOI: 10.3390/cells11233805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 11/11/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
The kidney epithelial barrier has multifaceted functions in body fluids, electrolyte homeostasis, and urine production. The renal epithelial barrier (REB) frequently faces and challenges osmotic dynamics, which gives rise to osmotic pressure (a physical force). Osmotic pressure overloading can crack epithelial integrity and damage the REB. The endurance of REB to osmotic pressure forces remains obscure. LMO7 (LIM domain only 7) is a protein associated with the cell-cell junctional complex and cortical F-actin. Its upregulation was observed in cells cultured under hypertonic conditions. LMO7 is predominantly distributed in renal tubule epithelial cells. Hypertonic stimulation leads to LMO7 and F-actin assembly in the cortical stress fibers of renal epithelial cells. Hypertonic-isotonic alternation, as a pressure force pushing the plasma membrane inward/outward, was set as osmotic disturbance and was applied to test FAK signaling and LMO7 functioning in maintaining junctional integrity. LMO7 depletion in cells resulted in junctional integrity loss in the epithelial sheet-cultured hypertonic medium or hypertonic-isotonic alternation. Conversely, FAK inhibition by PF-573228 led to failure in robust cortical F-actin assembly and LMO7 association with cortical F-actin in epithelial cells responding to hypertonic stress. Epithelial integrity against osmotic stress and LMO7 and FAK signaling are involved in assembling robust cortical F-actin and maintaining junctional integrity. LMO7 elaborately manages FAK activation in renal epithelial cells, which was demonstrated excessive FAK activation present in LMO7 depleted NRK-52E cells and epithelial integrity loss when cells with LMO7 depletion were exposed to a hypertonic environment. Our data suggests that LMO7 regulates FAK activation and is responsible for maintaining REB under osmotic disturbance.
Collapse
Affiliation(s)
- Yen-Yi Zhen
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Chien-Hsing Wu
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang-Gung Memorial Hospital, Kaohsiung 83301, Taiwan
- College of Medicine, Chang-Gung University, Taoyuan 33303, Taiwan
| | - Hung-Chun Chen
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Eddy Essen Chang
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Jia-Jung Lee
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Wei-Yu Chen
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
- Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan 83701, Taiwan
| | - Jer-Ming Chang
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Pei-Yun Tseng
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- School of Post-Baccalaureate Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Yue-Fang Wang
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Chi-Chih Hung
- Division of Nephrology, Department of Internal medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence:
| |
Collapse
|
14
|
Epithelial cells sacrifice excess area to preserve fluidity in response to external mechanical stress. Commun Biol 2022; 5:855. [PMID: 35995827 PMCID: PMC9395404 DOI: 10.1038/s42003-022-03809-8] [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: 04/11/2022] [Accepted: 08/04/2022] [Indexed: 11/24/2022] Open
Abstract
Viscoelastic properties of epithelial cells subject to shape changes were monitored by indentation-retraction/relaxation experiments. MDCK II cells cultured on extensible polydimethylsiloxane substrates were laterally stretched and, in response, displayed increased cortex contractility and loss of excess surface area. Thereby, the cells preserve their fluidity but inevitably become stiffer. We found similar behavior in demixed cell monolayers of ZO-1/2 double knock down (dKD) cells, cells exposed to different temperatures and after removal of cholesterol from the plasma membrane. Conversely, the mechanical response of single cells adhered onto differently sized patches displays no visible rheological change. Sacrificing excess surface area allows the cells to respond to mechanical challenges without losing their ability to flow. They gain a new degree of freedom that permits resolving the interdependence of fluidity β on stiffness \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$${K}_{{{{{{{{\rm{A}}}}}}}}}^{0}$$\end{document}KA0. We also propose a model that permits to tell apart contributions from excess membrane area and excess cell surface area. The viscoelastic properties of cells subjected to external strain are assessed, showing that cells become stiffer but preserve fluidity by sacrificing their excess surface area.
Collapse
|
15
|
Force Estimation during Cell Migration Using Mathematical Modelling. J Imaging 2022; 8:jimaging8070199. [PMID: 35877643 PMCID: PMC9320649 DOI: 10.3390/jimaging8070199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/06/2022] [Accepted: 07/12/2022] [Indexed: 11/29/2022] Open
Abstract
Cell migration is essential for physiological, pathological and biomedical processes such as, in embryogenesis, wound healing, immune response, cancer metastasis, tumour invasion and inflammation. In light of this, quantifying mechanical properties during the process of cell migration is of great interest in experimental sciences, yet few theoretical approaches in this direction have been studied. In this work, we propose a theoretical and computational approach based on the optimal control of geometric partial differential equations to estimate cell membrane forces associated with cell polarisation during migration. Specifically, cell membrane forces are inferred or estimated by fitting a mathematical model to a sequence of images, allowing us to capture dynamics of the cell migration. Our approach offers a robust and accurate framework to compute geometric mechanical membrane forces associated with cell polarisation during migration and also yields geometric information of independent interest, we illustrate one such example that involves quantifying cell proliferation levels which are associated with cell division, cell fusion or cell death.
Collapse
|
16
|
Xie C, Habif JC, Ukhanov K, Uytingco CR, Zhang L, Campbell RJ, Martens JR. Reversal of ciliary mechanisms of disassembly rescues olfactory dysfunction in ciliopathies. JCI Insight 2022; 7:158736. [PMID: 35771640 PMCID: PMC9462494 DOI: 10.1172/jci.insight.158736] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 06/27/2022] [Indexed: 11/17/2022] Open
Abstract
Ciliopathies are a class of genetic diseases resulting in cilia dysfunction in multiple organ systems, including the olfactory system. Currently, there are no available curative treatments for olfactory dysfunction and other symptoms in ciliopathies. The loss or shortening of olfactory cilia, as seen in multiple mouse models of the ciliopathy Bardet–Biedl syndrome (BBS), results in olfactory dysfunction. However, the underlying mechanism of the olfactory cilia reduction is unknown, thus limiting the development of therapeutic approaches for BBS and other ciliopathies. Here, we demonstrated that phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], a phosphoinositide typically excluded from olfactory cilia, aberrantly redistributed into the residual cilia of BBS mouse models, which caused F-actin ciliary infiltration. Importantly, PI(4,5)P2 and F-actin were necessary for olfactory cilia shortening. Using a gene therapeutic approach, the hydrolyzation of PI(4,5)P2 by overexpression of inositol polyphosphate-5-phosphatase E (INPP5E) restored cilia length and rescued odor detection and odor perception in BBS. Together, our data indicate that PI(4,5)P2/F-actin–dependent cilia disassembly is a common mechanism contributing to the loss of olfactory cilia in BBS and provide valuable pan-therapeutic intervention targets for the treatment of ciliopathies.
Collapse
Affiliation(s)
- Chao Xie
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| | - Julien C Habif
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| | - Kirill Ukhanov
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| | - Cedric R Uytingco
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| | - Lian Zhang
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| | - Robert J Campbell
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| | - Jeffrey R Martens
- Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville, United States of America
| |
Collapse
|
17
|
Ono Y, Matsuzawa K, Ikenouchi J. mTORC2 suppresses cell death induced by hypo-osmotic stress by promoting sphingomyelin transport. J Cell Biol 2022; 221:213090. [PMID: 35319770 PMCID: PMC8952684 DOI: 10.1083/jcb.202106160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 12/28/2021] [Accepted: 01/24/2022] [Indexed: 11/22/2022] Open
Abstract
Epithelial cells are constantly exposed to osmotic stress. The influx of water molecules into the cell in a hypo-osmotic environment increases plasma membrane tension as it rapidly expands. Therefore, the plasma membrane must be supplied with membrane lipids since expansion beyond its elastic limit will cause the cell to rupture. However, the molecular mechanism to maintain a constant plasma membrane tension is not known. In this study, we found that the apical membrane selectively expands when epithelial cells are exposed to hypo-osmotic stress. This requires the activation of mTORC2, which enhances the transport of secretory vesicles containing sphingomyelin, the major lipid of the apical membrane. We further show that the mTORC2–Rab35 axis plays an essential role in the defense against hypotonic stress by promoting the degradation of the actin cortex through the up-regulation of PI(4,5)P2 metabolism, which facilitates the apical tethering of sphingomyelin-loaded vesicles to relieve plasma membrane tension.
Collapse
Affiliation(s)
- Yumiko Ono
- Department of Biology, Faculty of Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Kenji Matsuzawa
- Department of Biology, Faculty of Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| | - Junichi Ikenouchi
- Department of Biology, Faculty of Sciences, Kyushu University, Nishi-ku, Fukuoka, Japan
| |
Collapse
|
18
|
Miyano T, Suzuki A, Sakamoto N. Hyperosmotic stress induces epithelial-mesenchymal transition through rearrangements of focal adhesions in tubular epithelial cells. PLoS One 2021; 16:e0261345. [PMID: 34932568 PMCID: PMC8691603 DOI: 10.1371/journal.pone.0261345] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 11/30/2021] [Indexed: 01/06/2023] Open
Abstract
Epithelial-mesenchymal transition (EMT) of tubular epithelial cells is a hallmark of renal tubulointerstitial fibrosis and is associated with chronic renal injury as well as acute renal injury. As one of the incidences and risk factors for acute renal injury, increasing the osmolality in the proximal tubular fluid by administration of intravenous mannitol has been reported, but the detailed mechanisms remain unclear. Hyperosmotic conditions caused by mannitol in the tubular tissue may generate not only osmotic but also mechanical stresses, which are known to be able to induce EMT in epithelial cells, thereby contributing to renal injury. Herein, we investigate the effect of hyperosmolarity on EMT in tubular epithelial cells. Normal rat kidney (NRK)-52E cells were exposed to mannitol-induced hyperosmotic stress. Consequently, the hyperosmotic stress led to a reduced expression of the epithelial marker E-cadherin and an enhanced expression of the mesenchymal marker, α-smooth muscle actin (α-SMA), which indicates an initiation of EMT in NKR-52E cells. The hyperosmotic condition also induced time-dependent disassembly and rearrangements of focal adhesions (FAs) concomitant with changes in actin cytoskeleton. Moreover, prevention of FAs rearrangements by cotreatment with Y-27632, a Rho-associated protein kinase inhibitor, could abolish the effects of hyperosmotic mannitol treatment, thus attenuating the expression of α-SMA to the level in nontreated cells. These results suggest that hyperosmotic stress may induce EMT through FAs rearrangement in proximal tubular epithelial cells.
Collapse
Affiliation(s)
- Takashi Miyano
- Department of Mechanical Systems Engineering, Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan
- * E-mail: (TM); (NS)
| | - Atsushi Suzuki
- Department of Mechanical Systems Engineering, Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan
| | - Naoya Sakamoto
- Department of Mechanical Systems Engineering, Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan
- * E-mail: (TM); (NS)
| |
Collapse
|
19
|
Passive coupling of membrane tension and cell volume during active response of cells to osmosis. Proc Natl Acad Sci U S A 2021; 118:2103228118. [PMID: 34785592 PMCID: PMC8617515 DOI: 10.1073/pnas.2103228118] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2021] [Indexed: 12/25/2022] Open
Abstract
Tension is the force-opposing stretch of lipid membranes. It controls cell functions involving membranes. Membranes rupture above a tension threshold, causing cell death if tension is not properly buffered. However, how cell membrane tension is quantitatively regulated is unknown because it is difficult to measure. Using a fluorescent membrane tension probe, we explored the coupling between membrane tension and cell volume changes during osmosis. This coupling is described by an equilibrium theory linking tension to folding and unfolding of the membrane. This coupling is nevertheless actively regulated by cell components such as the cytoskeleton, ion transporters, and mTOR pathways. Our results highlight that cell volume regulation and membrane tension homeostasis are independent from the regulation of their coupling. During osmotic changes of their environment, cells actively regulate their volume and plasma membrane tension that can passively change through osmosis. How tension and volume are coupled during osmotic adaptation remains unknown, as their quantitative characterization is lacking. Here, we performed dynamic membrane tension and cell volume measurements during osmotic shocks. During the first few seconds following the shock, cell volume varied to equilibrate osmotic pressures inside and outside the cell, and membrane tension dynamically followed these changes. A theoretical model based on the passive, reversible unfolding of the membrane as it detaches from the actin cortex during volume increase quantitatively describes our data. After the initial response, tension and volume recovered from hypoosmotic shocks but not from hyperosmotic shocks. Using a fluorescent membrane tension probe (fluorescent lipid tension reporter [Flipper-TR]), we investigated the coupling between tension and volume during these asymmetric recoveries. Caveolae depletion and pharmacological inhibition of ion transporters and channels, mTORCs, and the cytoskeleton all affected tension and volume responses. Treatments targeting mTORC2 and specific downstream effectors caused identical changes to both tension and volume responses, their coupling remaining the same. This supports that the coupling of tension and volume responses to osmotic shocks is primarily regulated by mTORC2.
Collapse
|
20
|
Steinkühler J, Fonda P, Bhatia T, Zhao Z, Leomil FSC, Lipowsky R, Dimova R. Superelasticity of Plasma- and Synthetic Membranes Resulting from Coupling of Membrane Asymmetry, Curvature, and Lipid Sorting. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2102109. [PMID: 34569194 PMCID: PMC8564416 DOI: 10.1002/advs.202102109] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2021] [Revised: 08/20/2021] [Indexed: 06/13/2023]
Abstract
Biological cells are contained by a fluid lipid bilayer (plasma membrane, PM) that allows for large deformations, often exceeding 50% of the apparent initial PM area. Isolated lipids self-organize into membranes, but are prone to rupture at small (<2-4%) area strains, which limits progress for synthetic reconstitution of cellular features. Here, it is shown that by preserving PM structure and composition during isolation from cells, vesicles with cell-like elasticity can be obtained. It is found that these plasma membrane vesicles store significant area in the form of nanotubes in their lumen. These act as lipid reservoirs and are recruited by mechanical tension applied to the outer vesicle membrane. Both in experiment and theory, it is shown that a "superelastic" response emerges from the interplay of lipid domains and membrane curvature. This finding allows for bottom-up engineering of synthetic biomaterials that appear one magnitude softer and with threefold larger deformability than conventional lipid vesicles. These results open a path toward designing superelastic synthetic cells possessing the inherent mechanics of biological cells.
Collapse
Affiliation(s)
- Jan Steinkühler
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
- Present address:
Department of Biomedical EngineeringNorthwestern UniversityEvanstonIL60657USA
| | - Piermarco Fonda
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
| | - Tripta Bhatia
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
- Department of Physical SciencesIndian Institute of Science Education and Research MohaliSector 81, Knowledge City, ManauliSAS NagarPunjab140306India
| | - Ziliang Zhao
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
- Present address:
Leibniz Institute of Photonic TechnologyJena07745Germany
| | - Fernanda S. C. Leomil
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
- Departamento de BiofísicaUniversidade Federal de São PauloSão Paulo043039‐032Brazil
| | - Reinhard Lipowsky
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
| | - Rumiana Dimova
- Theory and Bio‐SystemsMax Planck Institute of Colloids and InterfacesScience Park GolmPotsdam14424Germany
| |
Collapse
|
21
|
Kasprzycka W, Trębińska-Stryjewska A, Lewandowski RB, Stępińska M, Osuchowska PN, Dobrzyńska M, Achour Y, Osuchowski ŁP, Starzyński J, Mierczyk Z, Trafny EA. Nanosecond Pulsed Electric Field Only Transiently Affects the Cellular and Molecular Processes of Leydig Cells. Int J Mol Sci 2021; 22:ijms222011236. [PMID: 34681896 PMCID: PMC8541366 DOI: 10.3390/ijms222011236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 12/11/2022] Open
Abstract
The purpose of this study was to verify whether the nanosecond pulsed electric field, not eliciting thermal effects, permanently changes the molecular processes and gene expression of Leydig TM3 cells. The cells were exposed to a moderate electric field (80 quasi-rectangular shape pulses, 60 ns pulse width, and an electric field of 14 kV/cm). The putative disturbances were recorded over 24 h. After exposure to the nanosecond pulsed electric field, a 19% increase in cell diameter, a loss of microvilli, and a 70% reduction in cell adhesion were observed. Some cells showed the nonapoptotic externalization of phosphatidylserine through the pores in the plasma membrane. The cell proportion in the subG1 phase increased by 8% at the expense of the S and G2/M phases, and the DNA was fragmented in a small proportion of the cells. The membrane mitochondrial potential and superoxide content decreased by 37% and 23%, respectively. Microarray’s transcriptome analysis demonstrated a negative transient effect on the expression of genes involved in oxidative phosphorylation, DNA repair, cell proliferation, and the overexpression of plasma membrane proteins. We conclude that nanosecond pulsed electric field affected the physiology and gene expression of TM3 cells transiently, with a noticeable heterogeneity of cellular responses.
Collapse
Affiliation(s)
- Wiktoria Kasprzycka
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Alicja Trębińska-Stryjewska
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Rafał Bogdan Lewandowski
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Małgorzata Stępińska
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Paulina Natalia Osuchowska
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Monika Dobrzyńska
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Yahia Achour
- Faculty of Electronics, Military University of Technology, 00-908 Warsaw, Poland; (Y.A.); (J.S.)
| | - Łukasz Paweł Osuchowski
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Jacek Starzyński
- Faculty of Electronics, Military University of Technology, 00-908 Warsaw, Poland; (Y.A.); (J.S.)
| | - Zygmunt Mierczyk
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
| | - Elżbieta Anna Trafny
- Biomedical Engineering Centre, Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland; (W.K.); (A.T.-S.); (R.B.L.); (M.S.); (P.N.O.); (M.D.); (Ł.P.O.); (Z.M.)
- Correspondence:
| |
Collapse
|
22
|
Adami BS, Diz FM, Oliveira Gonçalves GP, Reghelin CK, Scherer M, Dutra AP, Papaléo RM, de Oliveira JR, Morrone FB, Wieck A, Xavier LL. Morphological and mechanical changes induced by quercetin in human T24 bladder cancer cells. Micron 2021; 151:103152. [PMID: 34607251 DOI: 10.1016/j.micron.2021.103152] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 07/21/2021] [Accepted: 09/21/2021] [Indexed: 01/04/2023]
Abstract
Quercetin is a flavonoid found in a great variety of foods such as vegetables and fruits. This compound has been shown to inhibit the proliferation of various types of cancer cells, as well as the growth of tumors in animal models. In the present study, we analyze morphological and mechanical changes produced by quercetin in T24 bladder cancer cells. Decreased cell viability and cell number were observed following quercetin treatment at 40 μM and 60 μM, respectively, as observed by the MTT assay and trypan blue exclusion test, supporting the hypothesis of quercetin anticancer effect. These assays also allowed us to determine the 40, 60, and 80 μM quercetin concentrations for the following analyses, Lactate Dehydrogenase assay (LDH); Nuclear Morphometric Analysis (NMA); and atomic force microscopy (AFM). The LDH assay showed no cytotoxic effect of quercetin on T24 cancer cells. The AFM showed morphological changes following quercetin treatment, namely decreased cell body, cytoplasmic retraction, and membrane condensation. Following quercetin treatment, the NMA evidenced an increased percentage of nuclei characteristic to the apoptotic and senescence processes. Cells also presented biophysical alterations consistent with cell death by apoptosis, as increased roughness and aggregation of membrane proteins, in a dose-dependent manner. Cellular elasticity, obtained through force curves, showed increased stiffness after quercetin treatment. Data presented herein demonstrate, for the first time, in a quantitative and qualitative form, the morphological and mechanical alterations induced by quercetin on bladder cancer cells.
Collapse
Affiliation(s)
- Bruno Silveira Adami
- Laboratório de Biologia Celular e Tecidual, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Fernando Mendonça Diz
- Pós-Graduação em Engenharia e Tecnologia de Materiais, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil; Laboratório de Farmacologia Aplicada, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Gustavo Petry Oliveira Gonçalves
- Laboratório Central de Microscopia e Microanálise (LabCeMM), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Camille Kirinus Reghelin
- Laboratório de Pesquisa em Biofísica Celular e Inflamação, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Matheus Scherer
- Laboratório de Pesquisa em Biofísica Celular e Inflamação, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Artur Pereira Dutra
- Laboratório de Farmacologia Aplicada, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Ricardo Meurer Papaléo
- Centro Interdisciplinar de Nanociências e Micro-Nanotecnologia - NanoPUCRS, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Jarbas Rodrigues de Oliveira
- Laboratório de Pesquisa em Biofísica Celular e Inflamação, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Fernanda Bueno Morrone
- Laboratório de Farmacologia Aplicada, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| | - Andrea Wieck
- Laboratório de Biologia Celular e Tecidual, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil.
| | - Léder Leal Xavier
- Laboratório de Biologia Celular e Tecidual, Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil; Laboratório Central de Microscopia e Microanálise (LabCeMM), Pontifícia Universidade Católica do Rio Grande do Sul, PUCRS, Avenida Ipiranga, 6681, Porto Alegre, RS, CEP: 90619-900, Brazil
| |
Collapse
|
23
|
Zheng Y, Ding Y, Zheng X, Zhang C, Zhang Y, Xiang Y, Tong A. Long-Term Dynamic Imaging of Cellular Processes Using an AIE Lipid Order Probe in the Dual-Color Mode. Anal Chem 2021; 93:10272-10281. [PMID: 34219453 DOI: 10.1021/acs.analchem.1c01681] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Lipid order in the cytoplasm membrane of eukaryotic cells undergoes dynamic changes in almost all cellular processes. Dynamically monitoring these changes is of essential biological significance and remains challenging. This work provides the first aggregation-induced emission probe, TPNPDA-C15, with highly three-dimensional specificity to cell membranes for fluorescent imaging of lipid order of live cells. TPNPDA-C15 displays red fluorescence enhancement with the viscosity increase while emits yellow fluorescence when aggregates form. Imaging analyses of giant unilamellar vesicles and live cells under osmotic shock by the probe demonstrate its sensitive response to the degree of phospholipids packing on artificial and cell membranes. Taking advantage of its superior low photocytotoxicity and high photostability, TPNPDA-C15 is further applied for long-term dynamic imaging of entire live cell physiological processes including apoptosis, ferroptosis, and mitosis in the dual-color mode. With the analysis of fluorescence signal changes in the two fluorescence channels, TPNPDA-C15 serves as a robust fluorescent probe for the imaging study of cellular dynamics.
Collapse
Affiliation(s)
- Yue Zheng
- Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P. R. China
| | - Yiwen Ding
- Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P. R. China
| | - Xiaokun Zheng
- Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P. R. China
| | - Chu Zhang
- Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P. R. China
| | - Yanli Zhang
- Imaging Core Facility, Technology Center for Protein Science, Tsinghua University, Beijing 100084, P. R. China
| | - Yu Xiang
- Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P. R. China
| | - Aijun Tong
- Department of Chemistry, Beijing Key Laboratory for Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, P. R. China
| |
Collapse
|
24
|
Parvanian S, Zha H, Su D, Xi L, Jiu Y, Chen H, Eriksson JE, Cheng F. Exosomal Vimentin from Adipocyte Progenitors Protects Fibroblasts against Osmotic Stress and Inhibits Apoptosis to Enhance Wound Healing. Int J Mol Sci 2021; 22:ijms22094678. [PMID: 33925176 PMCID: PMC8125065 DOI: 10.3390/ijms22094678] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/20/2021] [Accepted: 04/20/2021] [Indexed: 11/28/2022] Open
Abstract
Mechanical stress following injury regulates the quality and speed of wound healing. Improper mechanotransduction can lead to impaired wound healing and scar formation. Vimentin intermediate filaments control fibroblasts’ response to mechanical stress and lack of vimentin makes cells significantly vulnerable to environmental stress. We previously reported the involvement of exosomal vimentin in mediating wound healing. Here we performed in vitro and in vivo experiments to explore the effect of wide-type and vimentin knockout exosomes in accelerating wound healing under osmotic stress condition. Our results showed that osmotic stress increases the size and enhances the release of exosomes. Furthermore, our findings revealed that exosomal vimentin enhances wound healing by protecting fibroblasts against osmotic stress and inhibiting stress-induced apoptosis. These data suggest that exosomes could be considered either as a stress modifier to restore the osmotic balance or as a conveyer of stress to induce osmotic stress-driven conditions.
Collapse
Affiliation(s)
- Sepideh Parvanian
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; (S.P.); (H.Z.); (D.S.); (L.X.); (H.C.)
- Faculty of Science and Engineering, Åbo Akademi University & Turku Bioscience Centre, 20520 Turku, Finland;
| | - Hualian Zha
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; (S.P.); (H.Z.); (D.S.); (L.X.); (H.C.)
| | - Dandan Su
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; (S.P.); (H.Z.); (D.S.); (L.X.); (H.C.)
| | - Lifang Xi
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; (S.P.); (H.Z.); (D.S.); (L.X.); (H.C.)
| | - Yaming Jiu
- Key Laboratory of Molecular Virology and Immunology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai 200031, China;
- Institute Pasteur of Shanghai and Institute of Pathogen Biology, University of Chinese Academy of Sciences, 52 Sanlihe Rd., Xicheng District, Beijing 100019, China
| | - Hongbo Chen
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; (S.P.); (H.Z.); (D.S.); (L.X.); (H.C.)
| | - John E. Eriksson
- Faculty of Science and Engineering, Åbo Akademi University & Turku Bioscience Centre, 20520 Turku, Finland;
| | - Fang Cheng
- School of Pharmaceutical Sciences (Shenzhen), Sun Yat-sen University, Shenzhen 518107, China; (S.P.); (H.Z.); (D.S.); (L.X.); (H.C.)
- Faculty of Science and Engineering, Åbo Akademi University & Turku Bioscience Centre, 20520 Turku, Finland;
- Correspondence:
| |
Collapse
|
25
|
Lee H, Bonin K, Guthold M. Human mammary epithelial cells in a mature, stratified epithelial layer flatten and stiffen compared to single and confluent cells. Biochim Biophys Acta Gen Subj 2021; 1865:129891. [PMID: 33689830 DOI: 10.1016/j.bbagen.2021.129891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 02/07/2021] [Accepted: 03/03/2021] [Indexed: 10/22/2022]
Abstract
BACKGROUND The epithelium forms a protective barrier against external biological, chemical and physical insults. So far, AFM-based, micro-mechanical measurements have only been performed on single cells and confluent cells, but not yet on cells in mature layers. METHODS Using a combination of atomic force, fluorescence and confocal microscopy, we determined the changes in stiffness, morphology and actin distribution of human mammary epithelial cells (HMECs) as they transition from single cells to confluency to a mature layer. RESULTS Single HMECs have a tall, round (planoconvex) morphology, have actin stress fibers at the base, have diffuse cortical actin, and have a stiffness of 1 kPa. Confluent HMECs start to become flatter, basal actin stress fibers start to disappear, and actin accumulates laterally where cells abut. Overall stiffness is still 1 kPa with two-fold higher stiffness in the abutting regions. As HMECs mature and form multilayered structures, cells on apical surfaces become flatter (apically more level), wider, and seven times stiffer (mean, 7 kPa) than single and confluent cells. The main drivers of these changes are actin filaments, as cells show strong actin accumulation in the regions where cells adjoin, and in the apical regions. CONCLUSIONS HMECs stiffen, flatten and redistribute actin upon transiting from single cells to mature, confluent layers. GENERAL SIGNIFICANCE Our findings advance the understanding of breast ductal morphogenesis and mechanical homeostasis.
Collapse
Affiliation(s)
- Hyunsu Lee
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Keith Bonin
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Martin Guthold
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA.
| |
Collapse
|
26
|
Božič B, Zemljič Jokhadar Š, Kristanc L, Gomišček G. Cell Volume Changes and Membrane Ruptures Induced by Hypotonic Electrolyte and Sugar Solutions. Front Physiol 2020; 11:582781. [PMID: 33364974 PMCID: PMC7750460 DOI: 10.3389/fphys.2020.582781] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 11/06/2020] [Indexed: 01/09/2023] Open
Abstract
The cell volume changes induced by hypotonic electrolyte and sucrose solutions were studied in Chinese-hamster-ovary epithelial cells. The effects in the solutions with osmolarities between 32 and 315 mosM/L and distilled water were analyzed using bright-field and fluorescence confocal microscopy. The changes of the cell volume, accompanied by the detachment of cells, the formation of blebs, and the occurrence of almost spherical vesicle-like cells (“cell-vesicles”), showed significant differences in the long-time responses of the cells in the electrolyte solutions compared with the sucrose-containing solutions. A theoretical model based on different permeabilities of ions and sucrose molecules and on the action of Na+/K+-ATPase pumps is applied. It is consistent with the observed temporal behavior of the cells’ volume and the occurrence of tension-induced membrane ruptures and explains lower long-time responses of the cells in the sucrose solutions.
Collapse
Affiliation(s)
- Bojan Božič
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Špela Zemljič Jokhadar
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
| | - Luka Kristanc
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - Gregor Gomišček
- Institute of Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.,Faculty of Health Sciences, University of Ljubljana, Ljubljana, Slovenia
| |
Collapse
|
27
|
Joseph JG, Osorio C, Yee V, Agrawal A, Liu AP. Complimentary action of structured and unstructured domains of epsin supports clathrin-mediated endocytosis at high tension. Commun Biol 2020; 3:743. [PMID: 33293652 PMCID: PMC7722716 DOI: 10.1038/s42003-020-01471-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Accepted: 11/05/2020] [Indexed: 12/14/2022] Open
Abstract
Membrane tension plays an inhibitory role in clathrin-mediated endocytosis (CME) by impeding the transition of flat plasma membrane to hemispherical clathrin-coated structures (CCSs). Membrane tension also impedes the transition of hemispherical domes to omega-shaped CCSs. However, CME is not completely halted in cells under high tension conditions. Here we find that epsin, a membrane bending protein which inserts its N-terminus H0 helix into lipid bilayer, supports flat-to-dome transition of a CCS and stabilizes its curvature at high tension. This discovery is supported by molecular dynamic simulation of the epsin N-terminal homology (ENTH) domain that becomes more structured when embedded in a lipid bilayer. In addition, epsin has an intrinsically disordered protein (IDP) C-terminus domain which induces membrane curvature via steric repulsion. Insertion of H0 helix into lipid bilayer is not sufficient for stable epsin recruitment. Epsin's binding to adaptor protein 2 and clathrin is critical for epsin's association with CCSs under high tension conditions, supporting the importance of multivalent interactions in CCSs. Together, our results support a model where the ENTH and unstructured IDP region of epsin have complementary roles to ensure CME initiation and CCS maturation are unimpeded under high tension environments.
Collapse
Affiliation(s)
- Jophin G Joseph
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Carlos Osorio
- Department of Mechanical Engineering, University of Houston, Houston, TX, USA
| | - Vivian Yee
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Ashutosh Agrawal
- Department of Mechanical Engineering, University of Houston, Houston, TX, USA
| | - Allen P Liu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI, USA.
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA.
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI, USA.
- Department of Biophysics, University of Michigan, Ann Arbor, MI, USA.
| |
Collapse
|
28
|
De Mel JU, Gupta S, Perera RM, Ngo L, Zolnierczuk P, Bleuel M, Pingali SV, Schneider GJ. Influence of External NaCl Salt on Membrane Rigidity of Neutral DOPC Vesicles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9356-9367. [PMID: 32672981 DOI: 10.1021/acs.langmuir.0c01004] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Sodium chloride (NaCl) is a very common molecule in biotic and abiotic aqueous environments. In both cases, variation of ionic strength is inevitable. In addition to the osmotic variation posed by such perturbations, the question of whether the interactions of monovalent ions Na+ and Cl-, especially with the neutral head groups of phospholipid membranes are impactful enough to change the membrane rigidity, is still not entirely understood. We investigated the dynamics of 1,2-di-(octadecenoyl)-sn-glycero-3-phosphocholine (DOPC) vesicles with zwitterionic neutral head groups in the fluid phase with increasing external salt concentration. At higher salt concentrations, we observe an increase in bending rigidity from neutron spin echo (NSE) spectroscopy and an increase in bilayer thickness from small-angle X-ray scattering (SAXS). We compared different models to distinguish membrane undulations, lipid tail motions, and the translational diffusion of the vesicles. All of the models indicate an increase in bending rigidity by a factor of 1.3-3.6. We demonstrate that even down to t > 10 ns and for Q > 0.07 Å-1, the observed NSE relaxation spectra are influenced by translational diffusion of the vesicles. For t < 5 ns, the lipid tail motion dominates the intermediate dynamic structure factor. As the salt concentration increases, this contribution diminishes. We introduced a time-dependent analysis for the bending rigidity that highlights only a limited Zilman-Granek time window in which the rigidity is physically meaningful.
Collapse
Affiliation(s)
- Judith U De Mel
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Sudipta Gupta
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Rasangi M Perera
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Ly Ngo
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Piotr Zolnierczuk
- Jülich Centre for Neutron Science (JCNS), Outstation at SNS, POB 2008, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Markus Bleuel
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8562, United States
| | - Sai Venkatesh Pingali
- Neutron Sciences Directorate, Oak Ridge National Laboratory (ORNL), POB 2008, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Gerald J Schneider
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
- Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| |
Collapse
|
29
|
Lohmann S, Giampietro C, Pramotton FM, Al‐Nuaimi D, Poli A, Maiuri P, Poulikakos D, Ferrari A. The Role of Tricellulin in Epithelial Jamming and Unjamming via Segmentation of Tricellular Junctions. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2001213. [PMID: 32775171 PMCID: PMC7404176 DOI: 10.1002/advs.202001213] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/18/2020] [Indexed: 06/11/2023]
Abstract
Collective cellular behavior in confluent monolayers supports physiological and pathological processes of epithelial development, regeneration, and carcinogenesis. Here, the attainment of a mature and static tissue configuration or the local reactivation of cell motility involve a dynamic regulation of the junctions established between neighboring cells. Tricellular junctions (tTJs), established at vertexes where three cells meet, are ideally located to control cellular shape and coordinate multicellular movements. However, their function in epithelial tissue dynamic remains poorly defined. To investigate the role of tTJs establishment and maturation in the jamming and unjamming transitions of epithelial monolayers, a semi-automatic image-processing pipeline is developed and validated enabling the unbiased and spatially resolved determination of the tTJ maturity state based on the localization of fluorescent reporters. The software resolves the variation of tTJ maturity accompanying collective transitions during tissue maturation, wound healing, and upon the adaptation to osmolarity changes. Altogether, this work establishes junctional maturity at tricellular contacts as a novel biological descriptor of collective responses in epithelial monolayers.
Collapse
Affiliation(s)
- Sophie Lohmann
- Laboratory of Thermodynamics in Emerging TechnologiesETH ZurichZurich8092Switzerland
| | - Costanza Giampietro
- EMPASwiss Federal Laboratories for Materials Science and TechnologyExperimental Continuum MechanicsDübendorf8600Switzerland
| | | | - Dunja Al‐Nuaimi
- Laboratory of Thermodynamics in Emerging TechnologiesETH ZurichZurich8092Switzerland
| | - Alessandro Poli
- IFOM‐ The FIRC Institute of Molecular OncologySpatiotemporal organization of the nucleus UnitMilan20139Italy
| | - Paolo Maiuri
- IFOM‐ The FIRC Institute of Molecular OncologySpatiotemporal organization of the nucleus UnitMilan20139Italy
| | - Dimos Poulikakos
- Laboratory of Thermodynamics in Emerging TechnologiesETH ZurichZurich8092Switzerland
| | - Aldo Ferrari
- Laboratory of Thermodynamics in Emerging TechnologiesETH ZurichZurich8092Switzerland
- EMPASwiss Federal Laboratories for Materials Science and TechnologyExperimental Continuum MechanicsDübendorf8600Switzerland
- Institute for Mechanical SystemsETH ZurichZürich8092Switzerland
| |
Collapse
|
30
|
da Silva RA, Ishikiriama BLC, Ribeiro Lopes MM, de Castro RD, Garcia CR, Porto VC, Santos CF, Neppelenbroek KH, Lara VS. Antifungal activity of Punicalagin-nystatin combinations against Candida albicans. Oral Dis 2020; 26:1810-1819. [PMID: 32583467 DOI: 10.1111/odi.13507] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 05/19/2020] [Accepted: 05/31/2020] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Oral candidiasis is the most common opportunistic fungal infection of oral mucosa and results from an overgrowth of Candida, especially Candida albicans. The potential anti-C. albicans and cytotoxicity of punicalagin (PCG), isolated from Punica granatum, alone or with nystatin (NYS) were evaluated. METHODS Activity of compounds alone or in combinations was determined against two C. albicans strains (ATCC 90028 and SC5314). Minimal inhibitory concentration (MIC)-50 and Minimum Fungicidal Concentration (MFC) were assessed by XTT assay and CFU counts, respectively. For combinations, determination of fractional inhibitory concentration index was performed. Ergosterol pathway was investigated as a possible PCG antifungal mechanism. Cytotoxicity assays were undertaken on human primary oral keratinocytes and gingival fibroblasts incubated with antifungal concentrations of PCG and/or NYS for 24 hr. RESULTS Combination of NYS and PCG increased antifungal efficacy, compared with compounds tested alone. Combinations 4 (PCG-6.25 μg/ml; NYS-3.9 μg/ml) and 5 (PCG-12.5 μg/ml; NYS-1.95 μg/ml) were more effective since they reduced the MIC-50 of PCG (50 μg/ml) by 8 and 4 times, respectively, increased the candidal inhibition and nullified the PCG cytotoxicity for keratinocytes. PCG antifungal mechanism did not involve ergosterol biosynthesis pathway. CONCLUSIONS The favorable outcomes for combination of PCG and NYS encourage further testing this therapeutic strategy against C. albicans.
Collapse
Affiliation(s)
- Rafaela Alves da Silva
- Integrated Research Center, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
| | | | | | - Ricardo Dias de Castro
- Department of Clinical and Social Dentistry, Federal University of Paraíba, Castelo Branco III, João Pessoa, Brazil
| | - Cindy Ruiz Garcia
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
| | - Vinicius Carvalho Porto
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
| | - Carlos Ferreira Santos
- Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
| | - Karin Hermana Neppelenbroek
- Department of Prosthodontics and Periodontics, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
| | - Vanessa Soares Lara
- Department of Surgery, Stomatology, Pathology and Radiology, Bauru School of Dentistry, University of São Paulo (USP), Bauru, Brazil
| |
Collapse
|
31
|
Wesén E, Lundmark R, Esbjörner EK. Role of Membrane Tension Sensitive Endocytosis and Rho GTPases in the Uptake of the Alzheimer's Disease Peptide Aβ(1-42). ACS Chem Neurosci 2020; 11:1925-1936. [PMID: 32497421 PMCID: PMC7497631 DOI: 10.1021/acschemneuro.0c00053] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Intraneuronal accumulation of amyloid-β (Aβ) is an early pathological signum of Alzheimer's disease, and compartments of the endolysosomal system have been implicated in both seeding and cell-cell propagation of Aβ aggregation. We have studied how clathrin-independent mechanisms contribute to Aβ endocytosis, exploring pathways that are sensitive to changes in membrane tension and the regulation of Rho GTPases. Using live cell confocal microscopy and flow cytometry, we show the uptake of monomeric Aβ(1-42) into endocytic vesicles and vacuole-like dilations, following relaxation of osmotic pressure-induced cell membrane tension. This indicates Aβ(1-42) uptake via clathrin independent carriers (CLICs), although overexpression of the bar-domain protein GRAF1, a key regulator of CLICs, had no apparent effect. We furthermore report reduced Aβ(1-42) uptake following overexpression of constitutively active forms of the Rho GTPases Cdc42 and RhoA, whereas modulation of Rac1, which is linked to macropinosome formation, had no effect. Our results confirm that uptake of Aβ(1-42) is clathrin- and dynamin-independent and point to the involvement of a new and distinct clathrin-independent endocytic mechanism which is similar to uptake via CLICs or macropinocytosis but that also appear to involve yet uncharacterized molecular players.
Collapse
Affiliation(s)
- Emelie Wesén
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96 Gothenburg, Sweden
| | - Richard Lundmark
- Department of Integrative Medical Biology, Umeå University, Umeå 901 87, Sweden
| | - Elin K. Esbjörner
- Division of Chemical Biology, Department of Biology and Biological Engineering, Chalmers University of Technology, Kemivägen 10, 412 96 Gothenburg, Sweden
| |
Collapse
|
32
|
Casula E, Traversari G, Fadda S, Klymenko OV, Kontoravdi C, Cincotti A. Modelling the osmotic behaviour of human mesenchymal stem cells. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2019.107296] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
33
|
Membrane tension regulates syndecan-1 expression through actin remodelling. Biochim Biophys Acta Gen Subj 2019; 1863:129413. [DOI: 10.1016/j.bbagen.2019.129413] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/22/2019] [Accepted: 08/07/2019] [Indexed: 01/21/2023]
|
34
|
Le Roux AL, Quiroga X, Walani N, Arroyo M, Roca-Cusachs P. The plasma membrane as a mechanochemical transducer. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180221. [PMID: 31431176 PMCID: PMC6627014 DOI: 10.1098/rstb.2018.0221] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/22/2019] [Indexed: 12/20/2022] Open
Abstract
Cells are constantly submitted to external mechanical stresses, which they must withstand and respond to. By forming a physical boundary between cells and their environment that is also a biochemical platform, the plasma membrane (PM) is a key interface mediating both cellular response to mechanical stimuli, and subsequent biochemical responses. Here, we review the role of the PM as a mechanosensing structure. We first analyse how the PM responds to mechanical stresses, and then discuss how this mechanical response triggers downstream biochemical responses. The molecular players involved in PM mechanochemical transduction include sensors of membrane unfolding, membrane tension, membrane curvature or membrane domain rearrangement. These sensors trigger signalling cascades fundamental both in healthy scenarios and in diseases such as cancer, which cells harness to maintain integrity, keep or restore homeostasis and adapt to their external environment. This article is part of a discussion meeting issue 'Forces in cancer: interdisciplinary approaches in tumour mechanobiology'.
Collapse
Affiliation(s)
- Anabel-Lise Le Roux
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona 08028, Spain
| | - Xarxa Quiroga
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona 08028, Spain
| | - Nikhil Walani
- LaCàN, Universitat Politècnica de Catalunya-BarcelonaTech, Spain
| | - Marino Arroyo
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona 08028, Spain
- LaCàN, Universitat Politècnica de Catalunya-BarcelonaTech, Spain
| | - Pere Roca-Cusachs
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona 08028, Spain
- Department of Biomedical Sciences, Universitat de Barcelona, Barcelona 08036, Spain
| |
Collapse
|
35
|
Stiffness of MDCK II Cells Depends on Confluency and Cell Size. Biophys J 2019; 116:2204-2211. [PMID: 31126583 DOI: 10.1016/j.bpj.2019.04.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/25/2019] [Accepted: 04/22/2019] [Indexed: 12/26/2022] Open
Abstract
Mechanical phenotyping of adherent cells has become a serious tool in cell biology to understand how cells respond to their environment and eventually to identify disease patterns such as the malignancy of cancer cells. In the steady state, homeostasis is of pivotal importance, and cells strive to maintain their internal stresses even in challenging environments and in response to external chemical and mechanical stimuli. However, a major problem exists in determining mechanical properties because many techniques, such as atomic force microscopy, that assess these properties of adherent cells locally can only address a limited number of cells and provide elastic moduli that vary substantially from cell to cell. The origin of this spread in stiffness values is largely unknown and might limit the significance of measurements. Possible reasons for the disparity are variations in cell shape and size, as well as biological reasons such as the cell cycle or polarization state of the cell. Here, we show that stiffness of adherent epithelial cells rises with increasing projected apical cell area in a nonlinear fashion. This size stiffening not only occurs as a consequence of varying cell-seeding densities, it can also be observed within a small area of a particular cell culture. Experiments with single adherent cells attached to defined areas via microcontact printing show that size stiffening is limited to cells of a confluent monolayer. This leads to the conclusion that cells possibly regulate their size distribution through cortical stress, which is enhanced in larger cells and reduced in smaller cells.
Collapse
|
36
|
Ayee MAA, LeMaster E, Teng T, Lee J, Levitan I. Hypotonic Challenge of Endothelial Cells Increases Membrane Stiffness with No Effect on Tether Force. Biophys J 2019; 114:929-938. [PMID: 29490252 DOI: 10.1016/j.bpj.2017.12.032] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/20/2017] [Accepted: 12/27/2017] [Indexed: 01/13/2023] Open
Abstract
Regulation of cell volume is a fundamental property of all mammalian cells. Multiple signaling pathways are known to be activated by cell swelling and to contribute to cell volume homeostasis. Although cell mechanics and membrane tension have been proposed to couple cell swelling to signaling pathways, the impact of swelling on cellular biomechanics and membrane tension have yet to be fully elucidated. In this study, we use atomic force microscopy under isotonic and hypotonic conditions to measure mechanical properties of endothelial membranes including membrane stiffness, which reflects the stiffness of the submembrane cytoskeleton complex, and the force required for membrane tether formation, reflecting membrane tension and membrane-cytoskeleton attachment. We find that hypotonic swelling results in significant stiffening of the endothelial membrane without a change in membrane tension/membrane-cytoskeleton attachment. Furthermore, depolymerization of F-actin, which, as expected, results in a dramatic decrease in the cellular elastic modulus of both the membrane and the deeper cytoskeleton, indicating a collapse of the cytoskeleton scaffold, does not abrogate swelling-induced stiffening of the membrane. Instead, this swelling-induced stiffening of the membrane is enhanced. We propose that the membrane stiffening should be attributed to an increase in hydrostatic pressure that results from an influx of solutes and water into the cells. Most importantly, our results suggest that increased hydrostatic pressure, rather than changes in membrane tension, could be responsible for activating volume-sensitive mechanisms in hypotonically swollen cells.
Collapse
Affiliation(s)
- Manuela Aseye Ayele Ayee
- Division of Pulmonary, Critical Care, Sleep, and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Elizabeth LeMaster
- Division of Pulmonary, Critical Care, Sleep, and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois
| | - Tao Teng
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
| | - James Lee
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
| | - Irena Levitan
- Division of Pulmonary, Critical Care, Sleep, and Allergy, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois.
| |
Collapse
|
37
|
Membrane Curvature and Tension Control the Formation and Collapse of Caveolar Superstructures. Dev Cell 2019; 48:523-538.e4. [DOI: 10.1016/j.devcel.2018.12.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 07/24/2018] [Accepted: 12/14/2018] [Indexed: 01/13/2023]
|
38
|
Kristanc L, Božič B, Jokhadar ŠZ, Dolenc MS, Gomišček G. The pore-forming action of polyenes: From model membranes to living organisms. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:418-430. [DOI: 10.1016/j.bbamem.2018.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 11/04/2018] [Accepted: 11/14/2018] [Indexed: 01/05/2023]
|
39
|
Kamprad N, Witt H, Schröder M, Kreis CT, Bäumchen O, Janshoff A, Tarantola M. Adhesion strategies of Dictyostelium discoideum- a force spectroscopy study. NANOSCALE 2018; 10:22504-22519. [PMID: 30480299 DOI: 10.1039/c8nr07107a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Biological adhesion is essential for all motile cells and generally limits locomotion to suitably functionalized substrates displaying a compatible surface chemistry. However, organisms that face vastly varying environmental challenges require a different strategy. The model organism Dictyostelium discoideum (D.d.), a slime mould dwelling in the soil, faces the challenge of overcoming variable chemistry by employing the fundamental forces of colloid science. To understand the origin of D.d. adhesion, we realized and modified a variety of conditions for the amoeba comprising the absence and presence of the specific adhesion protein Substrate Adhesion A (sadA), glycolytic degradation, ionic strength, surface hydrophobicity and strength of van der Waals interactions by generating tailored model substrates. By employing AFM-based single cell force spectroscopy we could show that experimental force curves upon retraction exhibit two regimes. The first part up to the critical adhesion force can be described in terms of a continuum model, while the second regime of the curve beyond the critical adhesion force is governed by stochastic unbinding of individual binding partners and bond clusters. We found that D.d. relies on adhesive interactions based on EDL-DLVO (Electrical Double Layer-Derjaguin-Landau-Verwey-Overbeek) forces and contributions from the glycocalix and specialized adhesion molecules like sadA. This versatile mechanism allows the cells to adhere to a large variety of natural surfaces under various conditions.
Collapse
Affiliation(s)
- Nadine Kamprad
- Max Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany.
| | | | | | | | | | | | | |
Collapse
|
40
|
Colom A, Derivery E, Soleimanpour S, Tomba C, Molin MD, Sakai N, González-Gaitán M, Matile S, Roux A. A fluorescent membrane tension probe. Nat Chem 2018; 10:1118-1125. [PMID: 30150727 PMCID: PMC6197433 DOI: 10.1038/s41557-018-0127-3] [Citation(s) in RCA: 280] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/25/2018] [Indexed: 12/24/2022]
Abstract
Cells and organelles are delimited by lipid bilayers in which high deformability is essential to many cell processes, including motility, endocytosis and cell division. Membrane tension is therefore a major regulator of the cell processes that remodel membranes, albeit one that is very hard to measure in vivo. Here we show that a planarizable push-pull fluorescent probe called FliptR (fluorescent lipid tension reporter) can monitor changes in membrane tension by changing its fluorescence lifetime as a function of the twist between its fluorescent groups. The fluorescence lifetime depends linearly on membrane tension within cells, enabling an easy quantification of membrane tension by fluorescence lifetime imaging microscopy. We further show, using model membranes, that this linear dependency between lifetime of the probe and membrane tension relies on a membrane-tension-dependent lipid phase separation. We also provide calibration curves that enable accurate measurement of membrane tension using fluorescence lifetime imaging microscopy.
Collapse
Affiliation(s)
- Adai Colom
- Biochemistry Department, University of Geneva, Geneva, Switzerland
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Emmanuel Derivery
- Biochemistry Department, University of Geneva, Geneva, Switzerland
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge, UK
| | - Saeideh Soleimanpour
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Caterina Tomba
- Biochemistry Department, University of Geneva, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Marta Dal Molin
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Naomi Sakai
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Marcos González-Gaitán
- Biochemistry Department, University of Geneva, Geneva, Switzerland
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Stefan Matile
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland
| | - Aurélien Roux
- Biochemistry Department, University of Geneva, Geneva, Switzerland.
- Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, Switzerland.
- School of Chemistry and Biochemistry, University of Geneva, Geneva, Switzerland.
| |
Collapse
|
41
|
Marcotti S, Maki K, Reilly GC, Lacroix D, Adachi T. Hyaluronic acid selective anchoring to the cytoskeleton: An atomic force microscopy study. PLoS One 2018; 13:e0206056. [PMID: 30359403 PMCID: PMC6201909 DOI: 10.1371/journal.pone.0206056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/07/2018] [Indexed: 11/19/2022] Open
Abstract
The hyaluronic acid component of the glycocalyx plays a role in cell mechanotransduction by selectively transmitting mechanical signals to the cell cytoskeleton or to the cell membrane. The aim of this study was to evaluate the mechanical link between the hyaluronic acid molecule and the cell cytoskeleton by means of atomic force microscopy single molecule force spectroscopy. Hyaluronic acid molecules on live cells were targeted with probes coated with hyaluronic acid binding protein. Two different types of events were observed when the detachment of the target molecule from the probe occurred, suggesting the presence of cytoskeleton- and membrane-anchored molecules. Membrane-anchored molecules facilitated the formation of tethers when pulled. About 15% of the tested hyaluronic acid molecules were shown to be anchored to the cytoskeleton. When multiple molecules bonded to the probe, specific detachment patterns were observed, suggesting that a cytoskeletal bond needed to be broken to improve the ability to pull tethers from the cell membrane. This likely resulted in the formation of tethering structures maintaining a cytoskeletal core similar to the ones observed for cells over-expressing HA synthases. The different observed rupture events were associated with separate mechanotransductive mechanisms in an analogous manner to that previously proposed for the endothelial glycocalyx. Single cytoskeleton anchored rupture events represent HA molecules linked to the cytoskeleton and therefore transmitting mechanical stimuli into the inner cell compartments. Single membrane tethers would conversely represent the glycocalyx molecules connected to areas of the membrane where an abundance of signalling molecules reside.
Collapse
Affiliation(s)
- Stefania Marcotti
- Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
- Randall Centre for Cell and Molecular Biophysics, King’s College London, London, United Kingdom
| | - Koichiro Maki
- Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
- Department of Mechanical Engineering, University of Tokyo, Tokyo, Japan
| | - Gwendolen C. Reilly
- Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Damien Lacroix
- Insigneo Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
| | - Taiji Adachi
- Department of Biosystems Science, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
| |
Collapse
|
42
|
Leikina E, Gamage DG, Prasad V, Goykhberg J, Crowe M, Diao J, Kozlov MM, Chernomordik LV, Millay DP. Myomaker and Myomerger Work Independently to Control Distinct Steps of Membrane Remodeling during Myoblast Fusion. Dev Cell 2018; 46:767-780.e7. [PMID: 30197239 DOI: 10.1016/j.devcel.2018.08.006] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 06/27/2018] [Accepted: 08/08/2018] [Indexed: 02/03/2023]
Abstract
Classic mechanisms for membrane fusion involve transmembrane proteins that assemble into complexes and dynamically alter their conformation to bend membranes, leading to mixing of membrane lipids (hemifusion) and fusion pore formation. Myomaker and Myomerger govern myoblast fusion and muscle formation but are structurally divergent from traditional fusogenic proteins. Here, we show that Myomaker and Myomerger independently mediate distinct steps in the fusion pathway, where Myomaker is involved in membrane hemifusion and Myomerger is necessary for fusion pore formation. Mechanistically, we demonstrate that Myomerger is required on the cell surface where its ectodomains stress membranes. Moreover, we show that Myomerger drives fusion completion in a heterologous system independent of Myomaker and that a Myomaker-Myomerger physical interaction is not required for function. Collectively, our data identify a stepwise cell fusion mechanism in myoblasts where different proteins are delegated to perform unique membrane functions essential for membrane coalescence.
Collapse
Affiliation(s)
- Evgenia Leikina
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dilani G Gamage
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Vikram Prasad
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Joanna Goykhberg
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Michael Crowe
- Department of Cancer Biology, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Jiajie Diao
- Department of Cancer Biology, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Michael M Kozlov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Leonid V Chernomordik
- Section on Membrane Biology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Douglas P Millay
- Division of Molecular Cardiovascular Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
| |
Collapse
|
43
|
Entropic forces drive clustering and spatial localization of influenza A M2 during viral budding. Proc Natl Acad Sci U S A 2018; 115:E8595-E8603. [PMID: 30150411 DOI: 10.1073/pnas.1805443115] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The influenza A matrix 2 (M2) transmembrane protein facilitates virion release from the infected host cell. In particular, M2 plays a role in the induction of membrane curvature and/or in the scission process whereby the envelope is cut upon virion release. Here we show using coarse-grained computer simulations that various M2 assembly geometries emerge due to an entropic driving force, resulting in compact clusters or linearly extended aggregates as a direct consequence of the lateral membrane stresses. Conditions under which these protein assemblies will cause the lipid membrane to curve are explored, and we predict that a critical cluster size is required for this to happen. We go on to demonstrate that under the stress conditions taking place in the cellular membrane as it undergoes large-scale membrane remodeling, the M2 protein will, in principle, be able to both contribute to curvature induction and sense curvature to line up in manifolds where local membrane line tension is high. M2 is found to exhibit linactant behavior in liquid-disordered-liquid-ordered phase-separated lipid mixtures and to be excluded from the liquid-ordered phase, in near-quantitative agreement with experimental observations. Our findings support a role for M2 in membrane remodeling during influenza viral budding both as an inducer and a sensor of membrane curvature, and they suggest a mechanism by which localization of M2 can occur as the virion assembles and releases from the host cell, independent of how the membrane curvature is produced.
Collapse
|
44
|
Membrane Stiffening in Osmotic Swelling: Analysis of Membrane Tension and Elastic Modulus. CURRENT TOPICS IN MEMBRANES 2018; 81:97-123. [PMID: 30243442 DOI: 10.1016/bs.ctm.2018.07.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The effects of osmotic swelling on key cellular biomechanical properties are explored in this chapter. We present the governing equations and theoretical backgrounds of the models employed to estimate cell membrane tension and elastic moduli from experimental methods, and provide a summary of the prevailing experimental approaches used to obtain these biomechanical parameters. A detailed analysis of the current evidence of the effects of osmotic swelling on membrane tension and elastic moduli is provided. Briefly, due to the buffering effect of unfolding membrane reservoirs, mild hypotonic swelling does not change membrane tension or the adhesion of the membrane to the underlying cytoskeleton. Conversely, osmotic swelling causes the cell membrane envelope to stiffen, measured as an increase in the membrane elastic modulus.
Collapse
|
45
|
Liao HS, Wen PJ, Wu LG, Jin AJ. Effect of Osmotic Pressure on Cellular Stiffness as Evaluated Through Force Mapping Measurements. J Biomech Eng 2018. [DOI: 10.1115/1.4039378] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Atomic force microscopy (AFM) has been used to measure cellular stiffness at different osmolarities to investigate the effect of osmotic pressure on cells. However, substantial direct evidence is essential to clarify the phenomena derived from the experimental results. This study used both the single-point and force mapping methods to measure the effective Young's modulus of the cell by using temporal and spatial information. The single-point force measurements confirmed the positive correlation between cellular stiffness and osmolarity. The force mapping measurements provided local stiffness on the cellular surface and identified the cytoskeleton distribution underneath the plasma membrane. At hyper-osmolarity, the cytoskeleton was observed to cover most of the area underneath the plasma membrane, and the effective Young's modulus on the area with cytoskeleton support was determined to be higher than that at iso-osmolarity. The overall increase in cellular Young's modulus confirmed the occurrence of cytoskeleton compression at hyper-osmolarity. On the other hand, although the average Young's modulus at hypo-osmolarity was lower than that at iso-osmolarity, we observed that the local Young's modulus measured on the areas with cytoskeleton support remained similar from iso-osmolarity to hypo-osmolarity. The reduction of the average Young's modulus at hypo-osmolarity was attributed to reduced cytoskeleton coverage underneath the plasma membrane.
Collapse
Affiliation(s)
- Hsien-Shun Liao
- Department of Mechanical Engineering, National Taiwan University, Taipei 10617, Taiwan e-mail:
| | - Peter J. Wen
- National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892
| | - Ling-Gang Wu
- National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892
| | - Albert J. Jin
- National Institute of Biomedical Imaging and Bioengineering (NIBIB), Bethesda, MD 20892
| |
Collapse
|
46
|
Guo YC, Wang YX, Ge YP, Yu LJ, Guo J. Analysis of subcellular structural tension in axonal growth of neurons. Rev Neurosci 2018; 29:125-137. [DOI: 10.1515/revneuro-2017-0047] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 08/05/2017] [Indexed: 01/08/2023]
Abstract
AbstractThe growth and regeneration of axons are the core processes of nervous system development and functional recovery. They are also related to certain physiological and pathological conditions. For decades, it has been the consensus that a new axon is formed by adding new material at the growth cone. However, using the existing technology, we have studied the structural tension of the nerve cell, which led us to hypothesize that some subcellular structural tensions contribute synergistically to axonal growth and regeneration. In this review, we classified the subcellular structural tension, osmotic pressure, microfilament and microtubule-dependent tension involved controllably in promoting axonal growth. A squeezing model was built to analyze the mechanical mechanism underlying axonal elongation, which may provide a new view of axonal growth and inspire further research.
Collapse
|
47
|
Nehls S, Janshoff A. Elastic Properties of Pore-Spanning Apical Cell Membranes Derived from MDCK II Cells. Biophys J 2017; 113:1822-1830. [PMID: 29045876 DOI: 10.1016/j.bpj.2017.08.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 08/04/2017] [Accepted: 08/10/2017] [Indexed: 11/25/2022] Open
Abstract
The mechanical response of adherent, polarized cells to indentation is frequently attributed to the presence of an endogenous actin cortex attached to the inner leaflet of the plasma membrane. Here, we scrutinized the elastic properties of apical membranes separated from living cells and attached to a porous mesh in the absence of intracellular factors originating from the cytosol, organelles, the substrate, neighbors, and the nucleus. We found that a tension-based model describes the data very well providing essentially the prestress of the shell generated by adhesion of the apical membrane patches to the pore rim and the apparent area compressibility modulus, an intrinsic elastic modulus modulated by the surface excess stored in membrane reservoirs. Removal of membrane-associated proteins by proteases decreases the area compressibility modulus, whereas fixation and cross-linking of proteins with glutaraldehyde increases it.
Collapse
Affiliation(s)
- Stefan Nehls
- Georg-August-Universität Göttingen, Institute of Physical Chemistry, Göttingen, Germany
| | - Andreas Janshoff
- Georg-August-Universität Göttingen, Institute of Physical Chemistry, Göttingen, Germany.
| |
Collapse
|
48
|
Cartagena-Rivera AX, Van Itallie CM, Anderson JM, Chadwick RS. Apical surface supracellular mechanical properties in polarized epithelium using noninvasive acoustic force spectroscopy. Nat Commun 2017; 8:1030. [PMID: 29044161 PMCID: PMC5715111 DOI: 10.1038/s41467-017-01145-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 08/18/2017] [Indexed: 11/24/2022] Open
Abstract
Maintenance of epithelial tissue integrity requires coordination between cell–cell adherens junctions, tight junctions (TJ), and the perijunctional actomyosin cytoskeleton. Here we addressed the hypothesis that alterations in TJ structure and remodeling of the actomyosin cytoskeleton modify epithelial mechanics. Current methods to measure supracellular mechanical properties disrupt intact monolayers, therefore, we developed a novel method using noncontact acoustic frequency-modulation atomic force microscopy (FM-AFM) and tested it on MDCK polarized monolayers. Our results show that double knockdown (dKD) of ZO-1/ZO-2 elevates the apical epithelial tension and effective viscosity. Interestingly, epithelial tension is more sensitive to inhibition of myosin II ATPase activity than to inhibition of ROCK activity, but viscosity is highly sensitive to both. Additionally, we showed epithelial intercellular pulling forces at tricellular junctions and adhesion forces in dKD cells are elevated with an increase in contractility. In conclusion, FM-AFM enables the physiological and quantitative investigation of mechanics in intact epithelium. Determination of apical tension, fluidity, and intercellular adhesive forces in an epithelial monolayer are currently disruptive. Here the authors present a method using acoustic force microscopy to measure changes in these parameters upon tight junction structural alterations in a MDCK monolayer.
Collapse
Affiliation(s)
- Alexander X Cartagena-Rivera
- Section on Auditory Mechanics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Christina M Van Itallie
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - James M Anderson
- Laboratory of Tight Junction Structure and Function, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Richard S Chadwick
- Section on Auditory Mechanics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD, 20892, USA.
| |
Collapse
|
49
|
Clathrin-Independent Endocytosis Suppresses Cancer Cell Blebbing and Invasion. Cell Rep 2017; 20:1893-1905. [DOI: 10.1016/j.celrep.2017.08.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 06/15/2017] [Accepted: 07/28/2017] [Indexed: 01/09/2023] Open
|
50
|
Brückner BR, Nöding H, Janshoff A. Viscoelastic Properties of Confluent MDCK II Cells Obtained from Force Cycle Experiments. Biophys J 2017; 112:724-735. [PMID: 28256232 PMCID: PMC5340129 DOI: 10.1016/j.bpj.2016.12.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 12/01/2016] [Accepted: 12/15/2016] [Indexed: 01/04/2023] Open
Abstract
The local mechanical properties of cells are frequently probed by force indentation experiments carried out with an atomic force microscope. Application of common contact models provides a single parameter, the Young’s modulus, to describe the elastic properties of cells. The viscoelastic response of cells, however, is generally measured in separate microrheological experiments that provide complex shear moduli as a function of time or frequency. Here, we present a straightforward way to obtain rheological properties of cells from regular force distance curves collected in typical force indentation measurements. The method allows us to record the stress-strain relationship as well as changes in the weak power law of the viscoelastic moduli. We derive an analytical function based on the elastic-viscoelastic correspondence principle applied to Hertzian contact mechanics to model both indentation and retraction curves. Rheological properties are described by standard viscoelastic models and the paradigmatic weak power law found to interpret the viscoelastic properties of living cells best. We compare our method with atomic force microscopy-based active oscillatory microrheology and show that the method to determine the power law coefficient is robust against drift and largely independent of the indentation depth and indenter geometry. Cells were subject to Cytochalasin D treatment to provoke a drastic change in the power law coefficient and to demonstrate the feasibility of the approach to capture rheological changes extremely fast and precisely. The method is easily adaptable to different indenter geometries and acquires viscoelastic data with high spatiotemporal resolution.
Collapse
Affiliation(s)
| | - Helen Nöding
- Georg-August-Universität Göttingen, Institute of Physical Chemistry, Göttingen, Germany
| | - Andreas Janshoff
- Georg-August-Universität Göttingen, Institute of Physical Chemistry, Göttingen, Germany.
| |
Collapse
|