1
|
Della Rosa G, Gostynska N, Ephraim JW, Marras S, Moroni M, Tirelli N, Panuccio G, Palazzolo G. Magnesium vs. sodium alginate as precursors of calcium alginate: Mechanical differences and advantages in the development of functional neuronal networks. Carbohydr Polym 2024; 342:122375. [PMID: 39048194 DOI: 10.1016/j.carbpol.2024.122375] [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: 02/27/2024] [Revised: 06/04/2024] [Accepted: 06/05/2024] [Indexed: 07/27/2024]
Abstract
Calcium alginate is one of the most widely employed matrices in regenerative medicine. A downside is its heterogeneity, due to the poorly controllable character of the gelation of sodium alginate (NaAlg), i.e. the commonly used alginate salt, with calcium. Here, we have used magnesium alginate (MgAlg) as an alternative precursor of calcium alginate. MgAlg coils, more compact and thus less entangled than those of NaAlg, allow for an easier diffusion of calcium ions, whereas Mg is exchanged with calcium more slowly than Na; this allows for the formation of a material (Ca(Mg)Alg) with a more reversible creep behaviour than Ca(Na)Alg, due to a more homogeneous - albeit lower - density of elastically active cross-links. We also show that Ca(Mg)Alg supports better than Ca(Na)Alg the network development and function of embedded (rat cortical) neurons: they show greater neurite extension and branching at 7 and 21 days (Tubb3 and Map2 immunofluorescence) and better neuronal network functional maturation / more robust and longer-lasting activity, probed by calcium imaging and microelectrode array electrophysiology. Overall, our results unveil the potential of MgAlg as bioactive biomaterial for enabling the formation of functional neuron-based tissue analogues.
Collapse
Affiliation(s)
- Giulia Della Rosa
- Istituto Italiano di Tecnologia, Laboratory for Enhanced Regenerative Medicine, Genova, Italy; University of Pavia, Department of Molecular Medicine, Pavia, Italy.
| | - Natalia Gostynska
- Istituto Italiano di Tecnologia, Laboratory for Enhanced Regenerative Medicine, Genova, Italy.
| | - John W Ephraim
- Istituto Italiano di Tecnologia, Laboratory for Enhanced Regenerative Medicine, Genova, Italy.
| | - Sergio Marras
- Istituto Italiano di Tecnologia, Materials Characterization Facility, Genova, Italy.
| | | | - Nicola Tirelli
- Istituto Italiano di Tecnologia, Laboratory for Polymers and Biomaterials, Genova, Italy.
| | - Gabriella Panuccio
- Istituto Italiano di Tecnologia, Laboratory for Enhanced Regenerative Medicine, Genova, Italy.
| | - Gemma Palazzolo
- Istituto Italiano di Tecnologia, Laboratory for Enhanced Regenerative Medicine, Genova, Italy.
| |
Collapse
|
2
|
Cifuentes LP, Athamneh AIM, Efremov Y, Raman A, Kim T, Suter DM. A modified motor-clutch model reveals that neuronal growth cones respond faster to soft substrates. Mol Biol Cell 2024; 35:ar47. [PMID: 38354034 PMCID: PMC11064671 DOI: 10.1091/mbc.e23-09-0364] [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: 09/13/2023] [Revised: 02/02/2024] [Accepted: 02/05/2024] [Indexed: 02/27/2024] Open
Abstract
Neuronal growth cones sense a variety of cues including chemical and mechanical ones to establish functional connections during nervous system development. Substrate-cytoskeletal coupling is an established model for adhesion-mediated growth cone advance; however, the detailed molecular and biophysical mechanisms underlying the mechanosensing and mechanotransduction process remain unclear. Here, we adapted a motor-clutch model to better understand the changes in clutch and cytoskeletal dynamics, traction forces, and substrate deformation when a growth cone interacts with adhesive substrates of different stiffnesses. Model parameters were optimized using experimental data from Aplysia growth cones probed with force-calibrated glass microneedles. We included a reinforcement mechanism at both motor and clutch level. Furthermore, we added a threshold for retrograde F-actin flow that indicates when the growth cone is strongly coupled to the substrate. Our modeling results are in strong agreement with experimental data with respect to the substrate deformation and the latency time after which substrate-cytoskeletal coupling is strong enough for the growth cone to advance. Our simulations show that it takes the shortest time to achieve strong coupling when substrate stiffness was low at 4 pN/nm. Taken together, these results suggest that Aplysia growth cones respond faster and more efficiently to soft than stiff substrates.
Collapse
Affiliation(s)
| | | | - Yuri Efremov
- School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907
- Institute for Regenerative Medicine, Sechenov University, Moscow 119991, Russia
| | - Arvind Raman
- School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907
| | - Taeyoon Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907
| | - Daniel M. Suter
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907
- Purdue Institute for Inflammation, Immunology, and Infectious Disease, Purdue University, West Lafayette, IN 47907
- Bindley Bioscience Center, Purdue University, West Lafayette, IN 47907
| |
Collapse
|
3
|
Sarkar A, Niraula G, LeVine D, Zhao Y, Tu Y, Mollaeian K, Ren J, Que L, Wang X. Development of a Ratiometric Tension Sensor Exclusively Responding to Integrin Tension Magnitude in Live Cells. ACS Sens 2023; 8:3701-3712. [PMID: 37738233 PMCID: PMC10788086 DOI: 10.1021/acssensors.3c00606] [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] [Indexed: 09/24/2023]
Abstract
Integrin tensions are critical for cell mechanotransduction. By converting force to fluorescence, molecular tension sensors image integrin tensions in live cells with a high resolution. However, the fluorescence signal intensity results collectively from integrin tension magnitude, tension dwell time, integrin density, sensor accessibility, and so forth, making it highly challenging to specifically monitor the molecular force level of integrin tensions. Here, a ratiometric tension sensor (RTS) was developed to exclusively monitor the integrin tension magnitude. The RTS consists of two tension-sensing units that are coupled in series and always subject to the same integrin tension. These two units are activated by tension to fluoresce in separate spectra and with different activation rates. The ratio of their activation probabilities, reported by fluorescence ratiometric measurement, is solely determined by the local integrin tension magnitude. RTS responded sensitively to the variation of integrin tension magnitude in platelets and focal adhesions due to different cell plating times, actomyosin inhibition, or vinculin knockout. At last, RTS confirmed that integrin tension magnitude in platelets and focal adhesions decreases monotonically with the substrate rigidity, verifying the rigidity dependence of integrin tensions in live cells and suggesting that integrin tension magnitude could be a key biomechanical factor in cell rigidity sensing.
Collapse
Affiliation(s)
- Anwesha Sarkar
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
| | - Gopal Niraula
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
| | - Dana LeVine
- Department of Veterinary Clinical Sciences, Iowa State University, Ames, Iowa 50011, United States
| | - Yuanchang Zhao
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
| | - Ying Tu
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
| | - Keyvan Mollaeian
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Juan Ren
- Department of Mechanical Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Long Que
- Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011, United States
| | - Xuefeng Wang
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, United States
- Hoxworth Blood Center, College of Medicine, The University of Cincinnati, Cincinnati, Ohio 45219, United States
| |
Collapse
|
4
|
Abstract
Recently, substrate stiffness has been involved in the physiology and pathology of the nervous system. However, the role and function of substrate stiffness remain unclear. Here, we review known effects of substrate stiffness on nerve cell morphology and function in the central and peripheral nervous systems and their involvement in pathology. We hope this review will clarify the research status of substrate stiffness in nerve cells and neurological disorder.
Collapse
Affiliation(s)
- Weijin Si
- Key Laboratory of Cognitive Science, Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central Minzu University, Wuhan 430074, China
| | - Jihong Gong
- Key Laboratory of Cognitive Science, Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central Minzu University, Wuhan 430074, China
| | - Xiaofei Yang
- Key Laboratory of Cognitive Science, Hubei Key Laboratory of Medical Information Analysis and Tumor Diagnosis & Treatment, Laboratory of Membrane Ion Channels and Medicine, College of Biomedical Engineering, South-Central Minzu University, Wuhan 430074, China
| |
Collapse
|
5
|
Qin R, Melamed S, Yang B, Saxena M, Sheetz MP, Wolfenson H. Tumor Suppressor DAPK1 Catalyzes Adhesion Assembly on Rigid but Anoikis on Soft Matrices. Front Cell Dev Biol 2022; 10:959521. [PMID: 35927990 PMCID: PMC9343699 DOI: 10.3389/fcell.2022.959521] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 06/24/2022] [Indexed: 01/05/2023] Open
Abstract
Cancer cells normally grow on soft surfaces due to impaired mechanosensing of the extracellular matrix rigidity. Upon restoration of proper mechanosensing, cancer cells undergo apoptosis on soft surfaces (anoikis) like most normal cells. However, the link between mechanosensing and activation of anoikis is not clear. Here we show that death associated protein kinase 1 (DAPK1), a tumor suppressor that activates cell death, is directly linked to anoikis activation through rigidity sensing. We find that when rigidity sensing is decreased through inhibition of DAPK1 activity, cells are transformed for growth on soft matrices. Further, DAPK1 catalyzes matrix adhesion assembly and is part of adhesions on rigid surfaces. This pathway involves DAPK1 phosphorylation of tropomyosin1.1, the talin1 head domain, and tyrosine phosphorylation of DAPK1 by Src. On soft surfaces, DAPK1 rapidly dissociates from the adhesion complexes and activates apoptosis as catalyzed by PTPN12 activity and talin1 head. Thus, DAPK1 is important for adhesion assembly on rigid surfaces and the activation of anoikis on soft surfaces through its binding to rigidity-sensing modules.
Collapse
Affiliation(s)
- Ruifang Qin
- Department of Biological Sciences, Columbia University, New York City, NY, United States
| | - Shay Melamed
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion—Israel Institute of Technology, Haifa, Israel
| | - Bo Yang
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Mayur Saxena
- Department of Biomedical Engineering, Columbia University, New York City, NY, United States
| | - Michael P. Sheetz
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, United States
- *Correspondence: Haguy Wolfenson, ; Michael P. Sheetz,
| | - Haguy Wolfenson
- Department of Genetics and Developmental Biology, Rappaport Faculty of Medicine, Technion—Israel Institute of Technology, Haifa, Israel
- *Correspondence: Haguy Wolfenson, ; Michael P. Sheetz,
| |
Collapse
|
6
|
Procès A, Luciano M, Kalukula Y, Ris L, Gabriele S. Multiscale Mechanobiology in Brain Physiology and Diseases. Front Cell Dev Biol 2022; 10:823857. [PMID: 35419366 PMCID: PMC8996382 DOI: 10.3389/fcell.2022.823857] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 03/08/2022] [Indexed: 12/11/2022] Open
Abstract
Increasing evidence suggests that mechanics play a critical role in regulating brain function at different scales. Downstream integration of mechanical inputs into biochemical signals and genomic pathways causes observable and measurable effects on brain cell fate and can also lead to important pathological consequences. Despite recent advances, the mechanical forces that influence neuronal processes remain largely unexplored, and how endogenous mechanical forces are detected and transduced by brain cells into biochemical and genetic programs have received less attention. In this review, we described the composition of brain tissues and their pronounced microstructural heterogeneity. We discuss the individual role of neuronal and glial cell mechanics in brain homeostasis and diseases. We highlight how changes in the composition and mechanical properties of the extracellular matrix can modulate brain cell functions and describe key mechanisms of the mechanosensing process. We then consider the contribution of mechanobiology in the emergence of brain diseases by providing a critical review on traumatic brain injury, neurodegenerative diseases, and neuroblastoma. We show that a better understanding of the mechanobiology of brain tissues will require to manipulate the physico-chemical parameters of the cell microenvironment, and to develop three-dimensional models that can recapitulate the complexity and spatial diversity of brain tissues in a reproducible and predictable manner. Collectively, these emerging insights shed new light on the importance of mechanobiology and its implication in brain and nerve diseases.
Collapse
Affiliation(s)
- Anthony Procès
- Mechanobiology and Biomaterials group, Interfaces and Complex Fluids Laboratory, Research Institute for Biosciences, University of Mons, Mons, Belgium.,Neurosciences Department, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Marine Luciano
- Mechanobiology and Biomaterials group, Interfaces and Complex Fluids Laboratory, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Yohalie Kalukula
- Mechanobiology and Biomaterials group, Interfaces and Complex Fluids Laboratory, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Laurence Ris
- Neurosciences Department, Research Institute for Biosciences, University of Mons, Mons, Belgium
| | - Sylvain Gabriele
- Mechanobiology and Biomaterials group, Interfaces and Complex Fluids Laboratory, Research Institute for Biosciences, University of Mons, Mons, Belgium
| |
Collapse
|
7
|
Tomba C, Migdal C, Fuard D, Villard C, Nicolas A. Poly-l-lysine/Laminin Surface Coating Reverses Glial Cell Mechanosensitivity on Stiffness-Patterned Hydrogels. ACS APPLIED BIO MATERIALS 2022; 5:1552-1563. [PMID: 35274925 DOI: 10.1021/acsabm.1c01295] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Brain tissues demonstrate heterogeneous mechanical properties, which evolve with aging and pathologies. The observation in these tissues of smooth to sharp rigidity gradients raises the question of brain cell responses to both different values of rigidity and their spatial variations, in dependence on the surface chemistry they are exposed to. Here, we used recent techniques of hydrogel photopolymerization to achieve stiffness texturing down to micrometer resolution in polyacrylamide hydrogels. We investigated primary neuron adhesion and orientation as well as glial cell proliferative properties on these rigidity-textured hydrogels for two adhesive coatings: fibronectin or poly-l-lysine/laminin. Our main observation is that glial cell adhesion and proliferation is favored on the stiffer regions when the adhesive coating is fibronectin and on the softer ones when it consists of poly-l-lysine/laminin. This behavior was unchanged by the presence or the absence of neuronal cells. In addition, glial cells were not confined by sharp, micron-scaled gradients of rigidity. Our observations suggest that rigidity sensing could involve adhesion-related pathways that profoundly depend on surface chemistry.
Collapse
Affiliation(s)
- Caterina Tomba
- Univ. Grenoble Alps, CNRS, LTM, 38000 Grenoble, France.,Univ. Grenoble Alps, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
| | - Camille Migdal
- Univ. Grenoble Alps, CNRS, LTM, 38000 Grenoble, France.,Univ. Grenoble Alps, CEA, CNRS, Inserm, BIG-BCI, 38000 Grenoble, France.,Univ. Grenoble Alps, CEA, Inserm, BIG-BGE, 38000 Grenoble, France
| | - David Fuard
- Univ. Grenoble Alps, CNRS, LTM, 38000 Grenoble, France
| | - Catherine Villard
- Univ. Grenoble Alps, CNRS, Grenoble INP, Institut Néel, 38000 Grenoble, France
| | - Alice Nicolas
- Univ. Grenoble Alps, CNRS, LTM, 38000 Grenoble, France
| |
Collapse
|
8
|
Wang DY, Melero C, Albaraky A, Atherton P, Jansen KA, Dimitracopoulos A, Dajas-Bailador F, Reid A, Franze K, Ballestrem C. Vinculin is required for neuronal mechanosensing but not for axon outgrowth. Exp Cell Res 2021; 407:112805. [PMID: 34487728 DOI: 10.1016/j.yexcr.2021.112805] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 07/19/2021] [Accepted: 08/21/2021] [Indexed: 11/29/2022]
Abstract
Integrin receptors are transmembrane proteins that bind to the extracellular matrix (ECM). In most animal cell types integrins cluster together with adaptor proteins at focal adhesions that sense and respond to external mechanical signals. In the central nervous system (CNS), ECM proteins are sparsely distributed, the tissue is comparatively soft and neurons do not form focal adhesions. Thus, how neurons sense tissue stiffness is currently poorly understood. Here, we found that integrins and the integrin-associated proteins talin and focal adhesion kinase (FAK) are required for the outgrowth of neuronal processes. Vinculin, however, whilst not required for neurite outgrowth was a key regulator of integrin-mediated mechanosensing of neurons. During growth, growth cones of axons of CNS derived cells exerted dynamic stresses of around 10-12 Pa on their environment, and axons grew significantly longer on soft (0.4 kPa) compared to stiff (8 kPa) substrates. Depletion of vinculin blocked this ability of growth cones to distinguish between soft and stiff substrates. These data suggest that vinculin in neurons acts as a key mechanosensor, involved in the regulation of growth cone motility.
Collapse
Affiliation(s)
- De-Yao Wang
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Cristina Melero
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Ashwaq Albaraky
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Paul Atherton
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Oxford Road, Manchester, M13 9PT, UK; Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Manchester Academic Health Science Centre. Manchester, M13 9PT, UK
| | - Karin A Jansen
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Oxford Road, Manchester, M13 9PT, UK
| | - Andrea Dimitracopoulos
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3DY, UK
| | | | - Adam Reid
- Blond McIndoe Laboratories, Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Manchester Academic Health Science Centre. Manchester, M13 9PT, UK; Department of Plastic Surgery & Nurns, Wythenshawe Hospital, Manchester University NHS Foundation Trust. Manchester Academic Health Science Centre, Manchester, M23 9LT, UK
| | - Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Downing Street, Cambridge, CB2 3DY, UK; Institute of Medical Physics, Friedrich-Alexander University Erlangen-Nuremberg, 91052, Erlangen, Germany; Max-Planck-Zentrum für Physik und Medizin, 91054, Erlangen, Germany
| | - Christoph Ballestrem
- Division of Cell Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health. The University of Manchester, Oxford Road, Manchester, M13 9PT, UK.
| |
Collapse
|
9
|
Abe K, Baba K, Huang L, Wei KT, Okano K, Hosokawa Y, Inagaki N. Mechanosensitive axon outgrowth mediated by L1-laminin clutch interface. Biophys J 2021; 120:3566-3576. [PMID: 34384760 PMCID: PMC8456307 DOI: 10.1016/j.bpj.2021.08.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/28/2021] [Accepted: 08/04/2021] [Indexed: 11/11/2022] Open
Abstract
Mechanical properties of the extracellular environment modulate axon outgrowth. Growth cones at the tip of extending axons generate traction force for axon outgrowth by transmitting the force of actin filament retrograde flow, produced by actomyosin contraction and F-actin polymerization, to adhesive substrates through clutch and cell adhesion molecules. A molecular clutch between the actin filament flow and substrate is proposed to contribute to cellular mechanosensing. However, the molecular identity of the clutch interface responsible for mechanosensitive growth cone advance is unknown. We previously reported that mechanical coupling between actin filament retrograde flow and adhesive substrates through the clutch molecule shootin1a and the cell adhesion molecule L1 generates traction force for axon outgrowth and guidance. Here, we show that cultured mouse hippocampal neurons extend longer axons on stiffer substrates under elastic conditions that correspond to the soft brain environments. We demonstrate that this stiffness-dependent axon outgrowth requires actin-adhesion coupling mediated by shootin1a, L1, and laminin on the substrate. Speckle imaging analyses showed that L1 at the growth cone membrane switches between two adhesive states: L1 that is immobilized and that undergoes retrograde movement on the substrate. The duration of the immobilized phase was longer on stiffer substrates; this was accompanied by increases in actin-adhesion coupling and in the traction force exerted on the substrate. These data suggest that the interaction between L1 and laminin is enhanced on stiffer substrates, thereby promoting force generation for axon outgrowth.
Collapse
Affiliation(s)
- Kouki Abe
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Kentarou Baba
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Liguo Huang
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Koay Teng Wei
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Kazunori Okano
- Bio-processing Engineering Laboratory, Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Yoichiroh Hosokawa
- Bio-processing Engineering Laboratory, Division of Materials Science, Nara Institute of Science and Technology, Ikoma, Japan
| | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Japan.
| |
Collapse
|
10
|
Sevillano J, Sánchez-Alonso MG, Pizarro-Delgado J, Ramos-Álvarez MDP. Role of Receptor Protein Tyrosine Phosphatases (RPTPs) in Insulin Signaling and Secretion. Int J Mol Sci 2021; 22:ijms22115812. [PMID: 34071721 PMCID: PMC8198922 DOI: 10.3390/ijms22115812] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 01/12/2023] Open
Abstract
Changes in lifestyle in developed countries have triggered the prevalence of obesity and type 2 diabetes mellitus (T2DM) in the latest years. Consequently, these metabolic diseases associated to insulin resistance, and the morbidity associated with them, accounts for enormous costs for the health systems. The best way to face this problem is to identify potential therapeutic targets and/or early biomarkers to help in the treatment and in the early detection. In the insulin receptor signaling cascade, the activities of protein tyrosine kinases and phosphatases are coordinated, thus, protein tyrosine kinases amplify the insulin signaling response, whereas phosphatases are required for the regulation of the rate and duration of that response. The focus of this review is to summarize the impact of transmembrane receptor protein tyrosine phosphatase (RPTPs) in the insulin signaling cascade and secretion, and their implication in metabolic diseases such as obesity and T2DM.
Collapse
|
11
|
Momin A, Bahrampour S, Min HK, Chen X, Wang X, Sun Y, Huang X. Channeling Force in the Brain: Mechanosensitive Ion Channels Choreograph Mechanics and Malignancies. Trends Pharmacol Sci 2021; 42:367-384. [PMID: 33752907 DOI: 10.1016/j.tips.2021.02.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 02/15/2021] [Accepted: 02/26/2021] [Indexed: 12/15/2022]
Abstract
Force is everywhere. Through cell-intrinsic activities and interactions with the microenvironment, cells generate, transmit, and sense mechanical forces, such as compression, tension, and shear stress. These forces shape the mechanical properties of cells and tissues. Akin to how balanced biochemical signaling safeguards physiological processes, a mechanical optimum is required for homeostasis. The brain constructs a mechanical optimum from its cellular and extracellular constituents. However, in brain cancer, the mechanical properties are disrupted: tumor and nontumoral cells experience dysregulated solid and fluid stress, while tumor tissue develops altered stiffness. Mechanosensitive (MS) ion channels perceive mechanical cues to govern ion flux and cellular signaling. In this review, we describe the mechanical properties of the brain in healthy and cancer states and illustrate MS ion channels as sensors of mechanical cues to regulate malignant growth. Targeting MS ion channels offers disease insights at the interface of cancer, neuroscience, and mechanobiology to reveal therapeutic opportunities in brain tumors.
Collapse
Affiliation(s)
- Ali Momin
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ONT, M5S 3E1, Canada.
| | - Shahrzad Bahrampour
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, 171 77, Sweden
| | - Hyun-Kee Min
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ONT, M5S 3E1, Canada
| | - Xin Chen
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada
| | - Xian Wang
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada
| | - Yu Sun
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ONT, M5S 3G8, Canada
| | - Xi Huang
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children, Toronto, ONT, M5G 1X8, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ONT, M5S 3E1, Canada.
| |
Collapse
|
12
|
Javier-Torrent M, Zimmer-Bensch G, Nguyen L. Mechanical Forces Orchestrate Brain Development. Trends Neurosci 2020; 44:110-121. [PMID: 33203515 DOI: 10.1016/j.tins.2020.10.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/05/2020] [Accepted: 10/26/2020] [Indexed: 02/06/2023]
Abstract
During brain development, progenitors generate successive waves of neurons that populate distinct cerebral regions, where they settle and differentiate within layers or nuclei. While migrating and differentiating, neurons are subjected to mechanical forces arising from the extracellular matrix, and their interaction with neighboring cells. Changes in brain biomechanical properties, during its formation or aging, are converted in neural cells by mechanotransduction into intracellular signals that control key neurobiological processes. Here, we summarize recent findings that support the contribution of mechanobiology to neurodevelopment, with focus on the cerebral cortex. Also discussed are the existing toolbox and emerging technologies made available to assess and manipulate the physical properties of neurons and their environment.
Collapse
Affiliation(s)
- Míriam Javier-Torrent
- GIGA Stem Cells, GIGA-Neurosciences, University of Liège, CHU Sart Tilman, Liège 4000, Belgium
| | | | - Laurent Nguyen
- GIGA Stem Cells, GIGA-Neurosciences, University of Liège, CHU Sart Tilman, Liège 4000, Belgium.
| |
Collapse
|
13
|
Manipulation of Axonal Outgrowth via Exogenous Low Forces. Int J Mol Sci 2020; 21:ijms21218009. [PMID: 33126477 PMCID: PMC7663625 DOI: 10.3390/ijms21218009] [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] [Received: 09/17/2020] [Revised: 10/21/2020] [Accepted: 10/23/2020] [Indexed: 12/24/2022] Open
Abstract
Neurons are mechanosensitive cells. The role of mechanical force in the process of neurite initiation, elongation and sprouting; nerve fasciculation; and neuron maturation continues to attract considerable interest among scientists. Force is an endogenous signal that stimulates all these processes in vivo. The axon is able to sense force, generate force and, ultimately, transduce the force in a signal for growth. This opens up fascinating scenarios. How are forces generated and sensed in vivo? Which molecular mechanisms are responsible for this mechanotransduction signal? Can we exploit exogenously applied forces to mimic and control this process? How can these extremely low forces be generated in vivo in a non-invasive manner? Can these methodologies for force generation be used in regenerative therapies? This review addresses these questions, providing a general overview of current knowledge on the applications of exogenous forces to manipulate axonal outgrowth, with a special focus on forces whose magnitude is similar to those generated in vivo. We also review the principal methodologies for applying these forces, providing new inspiration and insights into the potential of this approach for future regenerative therapies.
Collapse
|
14
|
Conventional and Non-Conventional Roles of Non-Muscle Myosin II-Actin in Neuronal Development and Degeneration. Cells 2020; 9:cells9091926. [PMID: 32825197 PMCID: PMC7566000 DOI: 10.3390/cells9091926] [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: 07/20/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 12/13/2022] Open
Abstract
Myosins are motor proteins that use chemical energy to produce mechanical forces driving actin cytoskeletal dynamics. In the brain, the conventional non-muscle myosin II (NMII) regulates actin filament cytoskeletal assembly and contractile forces during structural remodeling of axons and dendrites, contributing to morphology, polarization, and migration of neurons during brain development. NMII isoforms also participate in neurotransmission and synaptic plasticity by driving actin cytoskeletal dynamics during synaptic vesicle release and retrieval, and formation, maturation, and remodeling of dendritic spines. NMIIs are expressed differentially in cerebral non-neuronal cells, such as microglia, astrocytes, and endothelial cells, wherein they play key functions in inflammation, myelination, and repair. Besides major efforts to understand the physiological functions and regulatory mechanisms of NMIIs in the nervous system, their contributions to brain pathologies are still largely unclear. Nonetheless, genetic mutations or deregulation of NMII and its regulatory effectors are linked to autism, schizophrenia, intellectual disability, and neurodegeneration, indicating non-conventional roles of NMIIs in cellular mechanisms underlying neurodevelopmental and neurodegenerative disorders. Here, we summarize the emerging biological roles of NMIIs in the brain, and discuss how actomyosin signaling contributes to dysfunction of neurons and glial cells in the context of neurological disorders. This knowledge is relevant for a deep understanding of NMIIs on the pathogenesis and therapeutics of neuropsychiatric and neurodegenerative diseases.
Collapse
|
15
|
Abstract
The brain is our most complex organ. During development, neurons extend axons, which may grow over long distances along well-defined pathways to connect to distant targets. Our current understanding of axon pathfinding is largely based on chemical signaling by attractive and repulsive guidance cues. These cues instruct motile growth cones, the leading tips of growing axons, where to turn and where to stop. However, it is not chemical signals that cause motion-motion is driven by forces. Yet our current understanding of the mechanical regulation of axon growth is very limited. In this review, I discuss the origin of the cellular forces controlling axon growth and pathfinding, and how mechanical signals encountered by growing axons may be integrated with chemical signals. This mechanochemical cross talk is an important but often overlooked aspect of cell motility that has major implications for many physiological and pathological processes involving neuronal growth.
Collapse
Affiliation(s)
- Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, United Kingdom;
| |
Collapse
|
16
|
Seo J, Youn W, Choi JY, Cho H, Choi H, Lanara C, Stratakis E, Choi IS. Neuro-taxis: Neuronal movement in gradients of chemical and physical environments. Dev Neurobiol 2020; 80:361-377. [PMID: 32304173 DOI: 10.1002/dneu.22749] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 04/13/2020] [Indexed: 12/15/2022]
Abstract
Environmental chemical and physical cues dynamically interact with migrating neurons and sprouting axons, and in particular, the gradients of environmental cues are regarded as one of the factors intimately involved in the neuronal movement. Since a growth cone was first described by Cajal, more than one century ago, chemical gradients have been suggested as one of the mechanisms by which the neurons determine proper paths and destinations. However, the gradients of physical cues, such as stiffness and topography, which also interact constantly with the neurons and their axons as a component of the extracellular environments, have rarely been noted regarding the guidance of neurons, despite their gradually increasingly reported influences in the case of nonneuronal-cell migration. In this review, we discuss chemical (i.e., chemo- and hapto-) and physical (i.e., duro-) taxis phenomena on the movement of neurons including axonal elongation. In addition, we suggest topotaxis, the most recently proposed physical-taxis phenomenon, as another potential mechanism in the neuronal movement, based on the reports of neuronal recognition of and responses to nanotopography.
Collapse
Affiliation(s)
| | - Wongu Youn
- Department of Chemistry, KAIST, Daejeon, Korea
| | - Ji Yu Choi
- Department of Chemistry, KAIST, Daejeon, Korea
| | | | | | - Christina Lanara
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Crete, Greece
| | - Emmanuel Stratakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), Heraklion, Crete, Greece.,Physics Department, University of Crete, Heraklion, Crete, Greece
| | - Insung S Choi
- Department of Chemistry, KAIST, Daejeon, Korea.,Department of Bio and Brain Engineering, KAIST, Daejeon, Korea
| |
Collapse
|
17
|
Nakazawa N, Kengaku M. Mechanical Regulation of Nuclear Translocation in Migratory Neurons. Front Cell Dev Biol 2020; 8:150. [PMID: 32226788 PMCID: PMC7080992 DOI: 10.3389/fcell.2020.00150] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/24/2020] [Indexed: 12/14/2022] Open
Abstract
Neuronal migration is a critical step during the formation of functional neural circuits in the brain. Newborn neurons need to move across long distances from the germinal zone to their individual sites of function; during their migration, they must often squeeze their large, stiff nuclei, against strong mechanical stresses, through narrow spaces in developing brain tissue. Recent studies have clarified how actomyosin and microtubule motors generate mechanical forces in specific subcellular compartments and synergistically drive nuclear translocation in neurons. On the other hand, the mechanical properties of the surrounding tissues also contribute to their function as an adhesive support for cytoskeletal force transmission, while they also serve as a physical barrier to nuclear translocation. In this review, we discuss recent studies on nuclear migration in developing neurons, from both cell and mechanobiological viewpoints.
Collapse
Affiliation(s)
- Naotaka Nakazawa
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study, Kyoto University, Kyoto, Japan
| | - Mineko Kengaku
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University Institute for Advanced Study, Kyoto University, Kyoto, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| |
Collapse
|
18
|
Zhong J, Yang Y, Liao L, Zhang C. Matrix stiffness-regulated cellular functions under different dimensionalities. Biomater Sci 2020; 8:2734-2755. [DOI: 10.1039/c9bm01809c] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The microenvironments that cells encounter with in vitro.
Collapse
Affiliation(s)
- Jiajun Zhong
- Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instruments (Sun Yat-sen University)
- School of Biomedical Engineering
- Sun Yat-Sen University
- Guangzhou
- P. R. China
| | - Yuexiong Yang
- Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instruments (Sun Yat-sen University)
- School of Biomedical Engineering
- Sun Yat-Sen University
- Guangzhou
- P. R. China
| | - Liqiong Liao
- Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering
- Biomaterials Research Center
- School of Biomedical Engineering
- Southern Medical University
- Guangzhou
| | - Chao Zhang
- Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instruments (Sun Yat-sen University)
- School of Biomedical Engineering
- Sun Yat-Sen University
- Guangzhou
- P. R. China
| |
Collapse
|
19
|
Abstract
Physical stimuli are essential for the function of eukaryotic cells, and changes in physical signals are important elements in normal tissue development as well as in disease initiation and progression. The complexity of physical stimuli and the cellular signals they initiate are as complex as those triggered by chemical signals. One of the most important, and the focus of this review, is the effect of substrate mechanical properties on cell structure and function. The past decade has produced a nearly exponentially increasing number of mechanobiological studies to define how substrate stiffness alters cell biology using both purified systems and intact tissues. Here we attempt to identify common features of mechanosensing in different systems while also highlighting the numerous informative exceptions to what in early studies appeared to be simple rules by which cells respond to mechanical stresses.
Collapse
Affiliation(s)
- Paul A Janmey
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of California-Berkeley, Berkeley, California; and Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Daniel A Fletcher
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of California-Berkeley, Berkeley, California; and Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Cynthia A Reinhart-King
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of California-Berkeley, Berkeley, California; and Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| |
Collapse
|
20
|
Nichol RH, Catlett TS, Onesto MM, Hollender D, Gómez TM. Environmental Elasticity Regulates Cell-type Specific RHOA Signaling and Neuritogenesis of Human Neurons. Stem Cell Reports 2019; 13:1006-1021. [PMID: 31708476 PMCID: PMC6915847 DOI: 10.1016/j.stemcr.2019.10.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 02/08/2023] Open
Abstract
The microenvironment of developing neurons is a dynamic landscape of both chemical and mechanical cues that regulate cell proliferation, differentiation, migration, and axon extension. While the regulatory roles of chemical ligands in neuronal morphogenesis have been described, little is known about how mechanical forces influence neurite development. Here, we tested how substratum elasticity regulates neurite development of human forebrain (hFB) neurons and human motor neurons (hMNs), two populations of neurons that naturally extend axons into distinct elastic environments. Using polyacrylamide and collagen hydrogels of varying compliance, we find that hMNs preferred rigid conditions that approximate the elasticity of muscle, whereas hFB neurons preferred softer conditions that approximate brain tissue elasticity. More stable leading-edge protrusions, increased peripheral adhesions, and elevated RHOA signaling of hMN growth cones contributed to faster neurite outgrowth on rigid substrata. Our data suggest that RHOA balances contractile and adhesive forces in response to substratum elasticity. Motor neurons derived from hiPSCs are tuned to grow optimally on rigid substrata hiPSCs derived forebrain neurons prefer softer substrata RHOA-dependent adhesion contributes to elasticity preferences Modulating RHOA affects axon development depending on substrata elasticity
Collapse
Affiliation(s)
- Robert H Nichol
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Neuroscience Training Program, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Timothy S Catlett
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Graduate Program in Cellular and Molecular Biology, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Massimo M Onesto
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Drew Hollender
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA
| | - Timothy M Gómez
- Department of Neuroscience, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Neuroscience Training Program, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA; Graduate Program in Cellular and Molecular Biology, University of Wisconsin School of Medicine and Public Health, WIMR II Room 5433, 1111 Highland Avenue, Madison, WI 53706, USA.
| |
Collapse
|
21
|
Chighizola M, Dini T, Lenardi C, Milani P, Podestà A, Schulte C. Mechanotransduction in neuronal cell development and functioning. Biophys Rev 2019; 11:701-720. [PMID: 31617079 PMCID: PMC6815321 DOI: 10.1007/s12551-019-00587-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/29/2019] [Indexed: 12/21/2022] Open
Abstract
Although many details remain still elusive, it became increasingly evident in recent years that mechanosensing of microenvironmental biophysical cues and subsequent mechanotransduction are strongly involved in the regulation of neuronal cell development and functioning. This review gives an overview about the current understanding of brain and neuronal cell mechanobiology and how it impacts on neurogenesis, neuronal migration, differentiation, and maturation. We will focus particularly on the events in the cell/microenvironment interface and the decisive extracellular matrix (ECM) parameters (i.e. rigidity and nanometric spatial organisation of adhesion sites) that modulate integrin adhesion complex-based mechanosensing and mechanotransductive signalling. It will also be outlined how biomaterial approaches mimicking essential ECM features help to understand these processes and how they can be used to control and guide neuronal cell behaviour by providing appropriate biophysical cues. In addition, principal biophysical methods will be highlighted that have been crucial for the study of neuronal mechanobiology.
Collapse
Affiliation(s)
- Matteo Chighizola
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Tania Dini
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Cristina Lenardi
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Paolo Milani
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Alessandro Podestà
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Carsten Schulte
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy.
| |
Collapse
|
22
|
Yu Y, Liu S, Wu X, Yu Z, Xu Y, Zhao W, Zavodnik I, Zheng J, Li C, Zhao H. Mechanism of Stiff Substrates up-Regulate Cultured Neuronal Network Activity. ACS Biomater Sci Eng 2019; 5:3475-3482. [PMID: 33405731 DOI: 10.1021/acsbiomaterials.9b00225] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Our previous work provided compelling evidence showing that substrate stiffness is crucial for regulating synaptic connectivity and excitatory synaptic transmission among neurons in the neuronal network. However, the underlying mechanisms remain elusive. In our study, polydimethylsiloxane (PDMS) substrates with different stiffness have been fabricated to investigate the mechanisms by which the substrate stiffness upregulates the formation and activity of the cultured neuronal network. Here we report that stiff substrate increased both the number of synapses and the efficacy of excitatory synaptic transmission. More colocalization of synaptotagmin and PSD-95 was observed in the neuronal network on stiff substrate, which indicated the synapse number has increased. We also found that the increased synapse number was mediated by Hevin and SPARC that are secreted from astrocyte. The increased efficacy of excitatory synaptic transmission induced by stiff substrate was explored in three aspects. First, stiff substrate enhanced the presynaptic activity through increasing the vesicular release probability (Pr) of neurotransmitters as well as the calcium influx. Second, stiff substrate reduced voltage-dependent Mg2+ blockade to N-methyl-d-aspartate receptor (NMDAR) channels, which led to higher postsynaptic activity. Third, our work suggested that the increased excitatory synaptic transmission in the neural network on stiff substrate involved the upregulated synaptic glutamate concentration. Taken together, these findings may provide a molecular mechanism underlying substrate stiffness regulation of excitatory synaptic transmission in the cultured neural network.
Collapse
Affiliation(s)
- Yang Yu
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Sisi Liu
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Xiaoan Wu
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, Florida 33136, United States
| | - Zhang Yu
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yishi Xu
- Beijing No. 4 High School, Beijing 100034, People's Republic of China
| | - Weijiang Zhao
- Center for Neuroscience, Shantou University Medical College, Shantou, Guangdong 515041, People's Republic of China
| | - Ilya Zavodnik
- Department of Biochemistry, Yanka Kupala State University Grodno, Blvd Len Kom 50, Grodno 230030, Belarus
| | - Jinping Zheng
- Department of Physiology, Changzhi Medical College, Changzhi 046000, People's Republic of China
| | - Chen Li
- Department of Physiology, Changzhi Medical College, Changzhi 046000, People's Republic of China
| | - Hucheng Zhao
- Institute of Biomechanics and Medical Engineering, School of Aerospace Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| |
Collapse
|
23
|
Response of mechanically-created neurites to extension. J Mech Behav Biomed Mater 2019; 98:121-130. [PMID: 31229904 DOI: 10.1016/j.jmbbm.2019.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 05/24/2019] [Accepted: 06/17/2019] [Indexed: 11/22/2022]
Abstract
We use micromanipulation techniques and real-time particle tracking to develop an approach to study specific attributes of neuron mechanics. We use a mechanical probe composed of a hollow micropipette with its tip fixed to a functionalized bead to induce the formation of a neurite in a sample of rat hippocampal neurons. We then move the sample relative to the pipette tip, elongating the neurite while simultaneously measuring its tension by optically tracking the deflection of the beaded tip. By calibrating the spring constant of the pipette, we can convert this deflection to a force. We use this technique to obtain uniaxial strain measurements of induced neurites and investigate the dependence of the force-extension relationship on mechanical pull speed. We show that in the range of pull speeds studied (0.05-1.8 μm/s), the variation in the work to extend a neurite 10 μm is consistent across pull speeds. We do not observe statistically significant rate-dependent effects in the force-extension profiles; instead we find the same quadratic behaviour (with parameters drawn from the same distributions) at each pull speed.
Collapse
|
24
|
Wen YQ, Gao X, Wang A, Yang Y, Liu S, Yu Z, Song GB, Zhao HC. Substrate stiffness affects neural network activity in an extracellular matrix proteins dependent manner. Colloids Surf B Biointerfaces 2018; 170:729-735. [DOI: 10.1016/j.colsurfb.2018.03.042] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/23/2018] [Accepted: 03/24/2018] [Indexed: 12/15/2022]
|
25
|
Seo J, Kim J, Joo S, Choi JY, Kang K, Cho WK, Choi IS. Nanotopography-Promoted Formation of Axon Collateral Branches of Hippocampal Neurons. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1801763. [PMID: 30028572 DOI: 10.1002/smll.201801763] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/23/2018] [Indexed: 06/08/2023]
Abstract
Axon collateral branches, as a key structural motif of neurons, allow neurons to integrate information from highly interconnected, divergent networks by establishing terminal boutons. Although physical cues are generally known to have a comprehensive range of effects on neuronal development, their involvement in axonal branching remains elusive. Herein, it is demonstrated that the nanopillar arrays significantly increase the number of axon collateral branches and also promote their growth. Immunostaining and biochemical analyses indicate that the physical interactions between the nanopillars and the neurons give rise to lateral filopodia at the axon shaft via cytoskeletal changes, leading to the formation of axonal branches. This report, demonstrates that nanotopography regulates axonal branching, and provides a guideline for the design of sophisticated neuron-based devices and scaffolds for neuro-engineering.
Collapse
Affiliation(s)
- Jeongyeon Seo
- Department of Chemistry, Center for Cell-Encapsulation Research, KAIST, Daejeon, 34141, South Korea
| | - Juan Kim
- Department of Chemistry, Center for Cell-Encapsulation Research, KAIST, Daejeon, 34141, South Korea
| | - Sunghoon Joo
- Department of Chemistry, Center for Cell-Encapsulation Research, KAIST, Daejeon, 34141, South Korea
| | - Ji Yu Choi
- Department of Chemistry, Center for Cell-Encapsulation Research, KAIST, Daejeon, 34141, South Korea
| | - Kyungtae Kang
- Department of Applied Chemistry, Kyung Hee University, Yongin, Gyeonggi, 17104, South Korea
| | - Woo Kyung Cho
- Department of Chemistry, Chungnam National University, Daejeon, 34134, South Korea
| | - Insung S Choi
- Department of Chemistry, Center for Cell-Encapsulation Research, KAIST, Daejeon, 34141, South Korea
| |
Collapse
|
26
|
Tanaka A, Fujii Y, Kasai N, Okajima T, Nakashima H. Regulation of neuritogenesis in hippocampal neurons using stiffness of extracellular microenvironment. PLoS One 2018; 13:e0191928. [PMID: 29408940 PMCID: PMC5800654 DOI: 10.1371/journal.pone.0191928] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 01/15/2018] [Indexed: 11/19/2022] Open
Abstract
The mechanosensitivity of neurons in the central nervous system (CNS) is an interesting issue as regards understanding neuronal development and designing compliant materials as neural interfaces between neurons and external devices for treating CNS injuries and disorders. Although neurite initiation from a cell body is known to be the first step towards forming a functional nervous network during development or regeneration, less is known about how the mechanical properties of the extracellular microenvironment affect neuritogenesis. Here, we investigated the filamentous actin (F-actin) cytoskeletal structures of neurons, which are a key factor in neuritogenesis, on gel substrates with a stiffness-controlled substrate, to reveal the relationship between substrate stiffness and neuritogenesis. We found that neuritogenesis was significantly suppressed on a gel substrate with an elastic modulus higher than the stiffness of in vivo brain. Fluorescent images of the F-actin cytoskeletal structures showed that the F-actin organization depended on the substrate stiffness. Circumferential actin meshworks and arcs were formed at the edge of the cell body on the stiff gel substrates unlike with soft substrates. The suppression of F-actin cytoskeleton formation improved neuritogenesis. The results indicate that the organization of neuronal F-actin cytoskeletons is strongly regulated by the mechanical properties of the surrounding environment, and the mechanically-induced F-actin cytoskeletons regulate neuritogenesis.
Collapse
Affiliation(s)
- Aya Tanaka
- NTT Basic Research Laboratories NTT Corporation, Atsugi, Kanagawa, Japan
- * E-mail:
| | - Yuki Fujii
- Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Nahoko Kasai
- NTT Basic Research Laboratories NTT Corporation, Atsugi, Kanagawa, Japan
| | - Takaharu Okajima
- Graduate School of Information Science and Technology, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Hiroshi Nakashima
- NTT Basic Research Laboratories NTT Corporation, Atsugi, Kanagawa, Japan
| |
Collapse
|
27
|
Rosso G, Young P, Shahin V. Implications of Schwann Cells Biomechanics and Mechanosensitivity for Peripheral Nervous System Physiology and Pathophysiology. Front Mol Neurosci 2017; 10:345. [PMID: 29118694 PMCID: PMC5660964 DOI: 10.3389/fnmol.2017.00345] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/11/2017] [Indexed: 12/21/2022] Open
Abstract
The presence of bones around the central nervous system (CNS) provides it with highly effective physiologically crucial mechanical protection. The peripheral nervous system (PNS), in contrast, lacks this barrier. Consequently, the long held belief is that the PNS is mechanically vulnerable. On the other hand, the PNS is exposed to a variety of physiological mechanical stresses during regular daily activities. This fact prompts us to question the dogma of PNS mechanical vulnerability. As a matter of fact, impaired mechanics of PNS nerves is associated with neuropathies with the liability to mechanical stresses paralleled by significant impairment of PNS physiological functions. Our recent biomechanical integrity investigations on nerve fibers from wild-type and neuropathic mice lend strong support in favor of natural mechanical protection of the PNS and demonstrate a key role of Schwann cells (SCs) therein. Moreover, recent works point out that SCs can sense mechanical properties of their microenvironment and the evidence is growing that SCs mechanosensitivity is important for PNS development and myelination. Hence, SCs exhibit mechanical strength necessary for PNS mechanoprotection as well as mechanosensitivity necessary for PNS development and myelination. This mini review reflects on the intriguing dual ability of SCs and implications for PNS physiology and pathophysiology.
Collapse
Affiliation(s)
- Gonzalo Rosso
- Institute of Physiology II, University of Münster, Münster, Germany
| | - Peter Young
- Department of Sleep Medicine and Neuromuscular Disorders, University of Münster, Münster, Germany
| | - Victor Shahin
- Institute of Physiology II, University of Münster, Münster, Germany
| |
Collapse
|
28
|
Li Y, Xiao Y, Liu C. The Horizon of Materiobiology: A Perspective on Material-Guided Cell Behaviors and Tissue Engineering. Chem Rev 2017; 117:4376-4421. [PMID: 28221776 DOI: 10.1021/acs.chemrev.6b00654] [Citation(s) in RCA: 345] [Impact Index Per Article: 49.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Although the biological functions of cell and tissue can be regulated by biochemical factors (e.g., growth factors, hormones), the biophysical effects of materials on the regulation of biological activity are receiving more attention. In this Review, we systematically summarize the recent progress on how biomaterials with controllable properties (e.g., compositional/degradable dynamics, mechanical properties, 2D topography, and 3D geometry) can regulate cell behaviors (e.g., cell adhesion, spreading, proliferation, cell alignment, and the differentiation or self-maintenance of stem cells) and tissue/organ functions. How the biophysical features of materials influence tissue/organ regeneration have been elucidated. Current challenges and a perspective on the development of novel materials that can modulate specific biological functions are discussed. The interdependent relationship between biomaterials and biology leads us to propose the concept of "materiobiology", which is a scientific discipline that studies the biological effects of the properties of biomaterials on biological functions at cell, tissue, organ, and the whole organism levels. This Review highlights that it is more important to develop ECM-mimicking biomaterials having a self-regenerative capacity to stimulate tissue regeneration, instead of attempting to recreate the complexity of living tissues or tissue constructs ex vivo. The principles of materiobiology may benefit the development of novel biomaterials providing combinative bioactive cues to activate the migration of stem cells from endogenous reservoirs (i.e., cell niches), stimulate robust and scalable self-healing mechanisms, and unlock the body's innate powers of regeneration.
Collapse
Affiliation(s)
- Yulin Li
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology , Meilong Road 130, Shanghai 200237, People's Republic of China
| | - Yin Xiao
- Institute of Health and Biomedical Innovation, Queensland University of Technology , Kelvin Grove, Brisbane, Queensland 4059, Australia
| | - Changsheng Liu
- Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology , Meilong Road 130, Shanghai 200237, People's Republic of China
| |
Collapse
|
29
|
Santos LC, Blair DA, Kumari S, Cammer M, Iskratsch T, Herbin O, Alexandropoulos K, Dustin ML, Sheetz MP. Actin polymerization-dependent activation of Cas-L promotes immunological synapse stability. Immunol Cell Biol 2016; 94:981-993. [PMID: 27359298 PMCID: PMC5121033 DOI: 10.1038/icb.2016.61] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 06/06/2016] [Accepted: 06/20/2016] [Indexed: 02/07/2023]
Abstract
The immunological synapse formed between a T-cell and an antigen-presenting cell is important for cell-cell communication during T-cell-mediated immune responses. Immunological synapse formation begins with stimulation of the T-cell receptor (TCR). TCR microclusters are assembled and transported to the center of the immunological synapse in an actin polymerization-dependent process. However, the physical link between TCR and actin remains elusive. Here we show that lymphocyte-specific Crk-associated substrate (Cas-L), a member of a force sensing protein family, is required for transport of TCR microclusters and for establishing synapse stability. We found that Cas-L is phosphorylated at TCR microclusters in an actin polymerization-dependent fashion. Furthermore, Cas-L participates in a positive feedback loop leading to amplification of Ca2+ signaling, inside-out integrin activation, and actomyosin contraction. We propose a new role for Cas-L in T-cell activation as a mechanical transducer linking TCR microclusters to the underlying actin network and coordinating multiple actin-dependent structures in the immunological synapse. Our studies highlight the importance of mechanotransduction processes in T-cell-mediated immune responses.
Collapse
Affiliation(s)
- Luís C Santos
- Department of Biological Sciences, Columbia UniversityNew YorkNYUSA
- Skirball Institute of Biomolecular Medicine, New York School of MedicineNew YorkNYUSA
- Icahn Medical Institute, Mount Sinai School of MedicineNew YorkNYUSA
| | - David A Blair
- Skirball Institute of Biomolecular Medicine, New York School of MedicineNew YorkNYUSA
| | - Sudha Kumari
- Skirball Institute of Biomolecular Medicine, New York School of MedicineNew YorkNYUSA
| | - Michael Cammer
- Skirball Institute of Biomolecular Medicine, New York School of MedicineNew YorkNYUSA
| | - Thomas Iskratsch
- Department of Biological Sciences, Columbia UniversityNew YorkNYUSA
| | - Olivier Herbin
- Icahn Medical Institute, Mount Sinai School of MedicineNew YorkNYUSA
| | | | - Michael L Dustin
- Skirball Institute of Biomolecular Medicine, New York School of MedicineNew YorkNYUSA
- Kennedy Institute of Rheumatology, University of OxfordHeadingtonUK
| | - Michael P Sheetz
- Department of Biological Sciences, Columbia UniversityNew YorkNYUSA
| |
Collapse
|
30
|
Mechanosensing is critical for axon growth in the developing brain. Nat Neurosci 2016; 19:1592-1598. [PMID: 27643431 PMCID: PMC5531257 DOI: 10.1038/nn.4394] [Citation(s) in RCA: 379] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 08/25/2016] [Indexed: 02/07/2023]
Abstract
During nervous system development, neurons extend axons along well-defined pathways. The current understanding of axon pathfinding is based mainly on chemical signaling. However, growing neurons interact not only chemically but also mechanically with their environment. Here we identify mechanical signals as important regulators of axon pathfinding. In vitro, substrate stiffness determined growth patterns of Xenopus retinal ganglion cell axons. In vivo atomic force microscopy revealed a noticeable pattern of stiffness gradients in the embryonic brain. Retinal ganglion cell axons grew toward softer tissue, which was reproduced in vitro in the absence of chemical gradients. To test the importance of mechanical signals for axon growth in vivo, we altered brain stiffness, blocked mechanotransduction pharmacologically and knocked down the mechanosensitive ion channel piezo1. All treatments resulted in aberrant axonal growth and pathfinding errors, suggesting that local tissue stiffness, read out by mechanosensitive ion channels, is critically involved in instructing neuronal growth in vivo.
Collapse
|
31
|
Thompson R, Chan C. Signal transduction of the physical environment in the neural differentiation of stem cells. TECHNOLOGY 2016; 4:1-8. [PMID: 27785459 PMCID: PMC5077250 DOI: 10.1142/s2339547816400070] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Neural differentiation is largely dependent on extracellular signals within the cell microenvironment. These extracellular signals are mainly in the form of soluble factors that activate intracellular signaling cascades that drive changes in the cell nucleus. However, it is becoming increasingly apparent that the physical microenvironment provides signals that can also influence lineage commitment and very low modulus surfaces has been repeatedly demonstrated to promote neurogenesis. The molecular mechanisms governing mechano-induced neural differentiation are still largely uncharacterized; however, a growing body of evidence indicates that physical stimuli can regulate known signaling cascades and transcription factors involved in neural differentiation. Understanding how the physical environment affects neural differentiation at the molecular level will enable research and design of materials that will eventually enhance neural stem cell (NSC) differentiation, homogeneity and specificity.
Collapse
Affiliation(s)
- Ryan Thompson
- Cell and Molecular Biology Program, East Lansing, Michigan 48824, USA
| | - Christina Chan
- Cell and Molecular Biology Program, East Lansing, Michigan 48824, USA; Department of Chemical Engineering and Materials Science, East Lansing, Michigan 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA
| |
Collapse
|
32
|
Lee HS, Ku B, Park TH, Park H, Choi JK, Chang KT, Kim CH, Ryu SE, Kim SJ. Identification of novel protein tyrosine phosphatase sigma inhibitors promoting neurite extension. Bioorg Med Chem Lett 2015; 26:87-93. [PMID: 26602279 DOI: 10.1016/j.bmcl.2015.11.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 10/26/2015] [Accepted: 11/09/2015] [Indexed: 10/22/2022]
Abstract
Protein tyrosine phosphatase sigma (PTPσ) is a potential target for the therapeutic treatment of neurological deficits associated with impaired neuronal recovery, as this protein is the receptor for chondroitin sulfate proteoglycan (CSPG), which is known to inhibit neuronal regeneration. Through a high-throughput screening approach started from 6400 representative compounds in the Korea Chemical Bank chemical library, we identified 11 novel PTPσ inhibitors that can be classified as flavonoid derivatives or analogs, with IC50 values ranging from 0.5 to 17.5μM. Biochemical assays and structure-based active site-docking simulation indicate that our inhibitors are accommodated at the catalytic active site of PTPσ as surrogates for the phosphotyrosine group. Treatments of these compounds on PC-12 neuronal cells led to the recovery of neurite extension attenuated by CSPG treatment, demonstrating their potential as antineurodegenerative agents.
Collapse
Affiliation(s)
- Hye Seon Lee
- Functional Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea; Department of Biology, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Bonsu Ku
- Functional Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea
| | - Tae Hyun Park
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul 133-791, Republic of Korea
| | - Hwangseo Park
- Department of Bioscience and Biotechnology, Sejong University, Seoul 143-747, Republic of Korea
| | - Joong-Kwon Choi
- Korea Chemical Bank, Korea Research Institute of Chemical Technology, Daejeon 305-600, Republic of Korea
| | - Kyu-Tae Chang
- National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology, Cheongju 363-883, Republic of Korea
| | - Cheol-Hee Kim
- Department of Biology, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Seong Eon Ryu
- Department of Bioengineering, College of Engineering, Hanyang University, Seoul 133-791, Republic of Korea
| | - Seung Jun Kim
- Functional Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Republic of Korea.
| |
Collapse
|
33
|
Polackwich RJ, Koch D, McAllister R, Geller HM, Urbach JS. Traction force and tension fluctuations in growing axons. Front Cell Neurosci 2015; 9:417. [PMID: 26578882 PMCID: PMC4624864 DOI: 10.3389/fncel.2015.00417] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/02/2015] [Indexed: 01/07/2023] Open
Abstract
Actively generated mechanical forces play a central role in axon growth and guidance, but the mechanisms that underly force generation and regulation in growing axons remain poorly understood. We report measurements of the dynamics of traction stresses from growth cones of actively advancing axons from postnatal rat DRG neurons. By tracking the movement of the growth cone and analyzing the traction stress field from a reference frame that moves with it, we are able to show that there is a clear and consistent average stress field that underlies the complex spatial stresses present at any one time. The average stress field has strong maxima on the sides of the growth cone, directed inward toward the growth cone neck. This pattern represents a contractile stress contained within the growth cone, and a net force that is balanced by the axon tension. Using high time-resolution measurements of the growth cone traction stresses, we show that the stress field is composed of fluctuating local stress peaks, with a large number peaks that live for a short time, a population of peaks whose lifetime distribution follows an exponential decay, and a small number of very long-lived peaks. We show that the high time-resolution data also reveal that the tension appears to vary randomly over short time scales, roughly consistent with the lifetime of the stress peaks, suggesting that the tension fluctuations originate from stochastic adhesion dynamics.
Collapse
Affiliation(s)
- Robert J Polackwich
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| | - Daniel Koch
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| | - Ryan McAllister
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| | - Herbert M Geller
- Developmental Neurobiology Section, Cell Biology and Physiology Center, National Heart, Lung, and Blood Institute, National Institutes of Health Bethesda, MD, USA
| | - Jeffrey S Urbach
- Department of Physics and The Institute for Soft Matter Synthesis and Metrology, Georgetown University Washington, DC, USA
| |
Collapse
|
34
|
Athamneh AIM, Suter DM. Quantifying mechanical force in axonal growth and guidance. Front Cell Neurosci 2015; 9:359. [PMID: 26441530 PMCID: PMC4584967 DOI: 10.3389/fncel.2015.00359] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/27/2015] [Indexed: 11/17/2022] Open
Abstract
Mechanical force plays a fundamental role in neuronal development, physiology, and regeneration. In particular, research has shown that force is involved in growth cone-mediated axonal growth and guidance as well as stretch-induced elongation when an organism increases in size after forming initial synaptic connections. However, much of the details about the exact role of force in these fundamental processes remain unknown. In this review, we highlight: (1) standing questions concerning the role of mechanical force in axonal growth and guidance; and (2) different experimental techniques used to quantify forces in axons and growth cones. We believe that satisfying answers to these questions will require quantitative information about the relationship between elongation, forces, cytoskeletal dynamics, axonal transport, signaling, substrate adhesion, and stiffness contributing to directional growth advance. Furthermore, we address why a wide range of force values have been reported in the literature, and what these values mean in the context of neuronal mechanics. We hope that this review will provide a guide for those interested in studying the role of force in development and regeneration of neuronal networks.
Collapse
Affiliation(s)
- Ahmad I M Athamneh
- Bindley Bioscience Center, Birck Nanotechnology Center, Department of Biological Sciences, Purdue University West Lafayette, IN, USA
| | - Daniel M Suter
- Bindley Bioscience Center, Birck Nanotechnology Center, Department of Biological Sciences, Purdue University West Lafayette, IN, USA
| |
Collapse
|
35
|
Abstract
Neuronal growth cones are exquisite sensory-motor machines capable of transducing features contacted in their local extracellular environment into guided process extension during development. Extensive research has shown that chemical ligands activate cell surface receptors on growth cones leading to intracellular signals that direct cytoskeletal changes. However, the environment also provides mechanical support for growth cone adhesion and traction forces that stabilize leading edge protrusions. Interestingly, recent work suggests that both the mechanical properties of the environment and mechanical forces generated within growth cones influence axon guidance. In this review we discuss novel molecular mechanisms involved in growth cone force production and detection, and speculate how these processes may be necessary for the development of proper neuronal morphogenesis.
Collapse
Affiliation(s)
- Patrick C Kerstein
- Neuroscience Training Program, Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison Madison, WI, USA
| | - Robert H Nichol
- Neuroscience Training Program, Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison Madison, WI, USA
| | - Timothy M Gomez
- Neuroscience Training Program, Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin-Madison Madison, WI, USA
| |
Collapse
|
36
|
Tamariz E, Varela-Echavarría A. The discovery of the growth cone and its influence on the study of axon guidance. Front Neuroanat 2015; 9:51. [PMID: 26029056 PMCID: PMC4432662 DOI: 10.3389/fnana.2015.00051] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 04/13/2015] [Indexed: 11/25/2022] Open
Abstract
For over a century, there has been a great deal of interest in understanding how neural connectivity is established during development and regeneration. Interest in the latter arises from the possibility that knowledge of this process can be used to re-establish lost connections after lesion or neurodegeneration. At the end of the XIX century, Santiago Ramón y Cajal discovered that the distal tip of growing axons contained a structure that he called the growth cone. He proposed that this structure enabled the axon's oriented growth in response to attractants, now known as chemotropic molecules. He further proposed that the physical properties of the surrounding tissues could influence the growth cone and the direction of growth. This seminal discovery afforded a plausible explanation for directed axonal growth and has led to the discovery of axon guidance mechanisms that include diffusible attractants and repellants and guidance cues anchored to cell membranes or extracellular matrix. In this review the major events in the development of this field are discussed.
Collapse
Affiliation(s)
- Elisa Tamariz
- Instituto de Ciencias de la Salud, Universidad VeracruzanaXalapa, Mexico
| | | |
Collapse
|
37
|
Molecular Mechanoneurobiology: An Emerging Angle to Explore Neural Synaptic Functions. BIOMED RESEARCH INTERNATIONAL 2015; 2015:486827. [PMID: 26106609 PMCID: PMC4461725 DOI: 10.1155/2015/486827] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Accepted: 03/17/2015] [Indexed: 12/28/2022]
Abstract
Neural synapses are intercellular asymmetrical junctions that transmit biochemical and biophysical information between a neuron and a target cell. They are very tight, dynamic, and well organized by many synaptic adhesion molecules, signaling receptors, ion channels, and their associated cytoskeleton that bear forces. Mechanical forces have been an emerging factor in regulating axon guidance and growth, synapse formation and plasticity in physiological and pathological brain activity. Therefore, mechanical forces are undoubtedly exerted on those synaptic molecules and modulate their functions. Here we review current progress on how mechanical forces regulate receptor-ligand interactions, protein conformations, ion channels activation, and cytoskeleton dynamics and discuss how these regulations potentially affect synapse formation, stabilization, and plasticity.
Collapse
|
38
|
Zhang QY, Zhang YY, Xie J, Li CX, Chen WY, Liu BL, Wu XA, Li SN, Huo B, Jiang LH, Zhao HC. Stiff substrates enhance cultured neuronal network activity. Sci Rep 2014; 4:6215. [PMID: 25163607 PMCID: PMC4147369 DOI: 10.1038/srep06215] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Accepted: 08/07/2014] [Indexed: 11/09/2022] Open
Abstract
The mechanical property of extracellular matrix and cell-supporting substrates is known to modulate neuronal growth, differentiation, extension and branching. Here we show that substrate stiffness is an important microenvironmental cue, to which mouse hippocampal neurons respond and integrate into synapse formation and transmission in cultured neuronal network. Hippocampal neurons were cultured on polydimethylsiloxane substrates fabricated to have similar surface properties but a 10-fold difference in Young's modulus. Voltage-gated Ca(2+) channel currents determined by patch-clamp recording were greater in neurons on stiff substrates than on soft substrates. Ca(2+) oscillations in cultured neuronal network monitored using time-lapse single cell imaging increased in both amplitude and frequency among neurons on stiff substrates. Consistently, synaptic connectivity recorded by paired recording was enhanced between neurons on stiff substrates. Furthermore, spontaneous excitatory postsynaptic activity became greater and more frequent in neurons on stiff substrates. Evoked excitatory transmitter release and excitatory postsynaptic currents also were heightened at synapses between neurons on stiff substrates. Taken together, our results provide compelling evidence to show that substrate stiffness is an important biophysical factor modulating synapse connectivity and transmission in cultured hippocampal neuronal network. Such information is useful in designing instructive scaffolds or supporting substrates for neural tissue engineering.
Collapse
Affiliation(s)
- Quan-You Zhang
- 1] Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China [2] College of Mechanics, Taiyuan University of Technology, China [3]
| | - Yan-Yan Zhang
- 1] Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China [2]
| | - Jing Xie
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Chen-Xu Li
- Medical School, Datong University, China
| | - Wei-Yi Chen
- College of Mechanics, Taiyuan University of Technology, China
| | - Bai-Lin Liu
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Xiao-an Wu
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| | - Shu-Na Li
- Biomechanics and Biomaterials Laboratory, Department of Applied Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, China
| | - Bo Huo
- Biomechanics and Biomaterials Laboratory, Department of Applied Mechanics, School of Aerospace Engineering, Beijing Institute of Technology, China
| | - Lin-Hua Jiang
- 1] School of Biomedical Sciences, University of Leeds, United Kingdom [2] Department of Physiology and Neurobiology, School of Basic Medical Sciences, Xinxiang Medical University, China
| | - Hu-Cheng Zhao
- Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, China
| |
Collapse
|
39
|
Mueller JK, Tyler WJ. A quantitative overview of biophysical forces impinging on neural function. Phys Biol 2014; 11:051001. [DOI: 10.1088/1478-3975/11/5/051001] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
40
|
Sur S, Guler MO, Webber MJ, Pashuck ET, Ito M, Stupp SI, Launey T. Synergistic regulation of cerebellar Purkinje neuron development by laminin epitopes and collagen on an artificial hybrid matrix construct. Biomater Sci 2014; 2:903-914. [PMID: 25530849 PMCID: PMC4269166 DOI: 10.1039/c3bm60228a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The extracellular matrix (ECM) creates a dynamic environment around the cells in the developing central nervous system, providing them with the necessary biochemical and biophysical signals. Although the functions of many ECM molecules in neuronal development have been individually studied in detail, the combinatorial effects of multiple ECM components are not well characterized. Here we demonstrate that the expression of collagen and laminin-1 (lam-1) are spatially and temporally correlated during embryonic and post-natal development of the cerebellum. These changes in ECM distribution correspond to specific stages of Purkinje neuron (PC) migration, somatic monolayer formation and polarization. To clarify the respective roles of these ECM molecules on PC development, we cultured cerebellar neurons on a hybrid matrix comprised of collagen and a synthetic peptide amphiphile nanofiber bearing a potent lam-1 derived bioactive IKVAV peptide epitope. By systematically varying the concentration and ratio of collagen and the laminin epitope in the matrix, we could demonstrate a synergistic relationship between these two ECM components in controlling multiple aspects of PC maturation. An optimal ratio of collagen and IKVAV in the matrix was found to promote maximal PC survival and dendrite growth, while dendrite penetration into the matrix was enhanced by a high IKVAV to collagen ratio. In addition, the laminin epitope was found to guide PC axon development. By combining our observations in vivo and in vitro, we propose a model of PC development where the synergistic effects of collagen and lam-1 play a key role in migration, polarization and morphological maturation of PCs.
Collapse
Affiliation(s)
- Shantanu Sur
- Laboratory for Memory and Learning, RIKEN Brain Science Institute, Wako-shi, 351-0198 Saitama, Japan
- School of Medical Science and Technology, IIT Kharagpur, 721302, India
- The Institute for Bionanotechnology in Medicine (IBNAM), Northwestern University, Chicago, IL 60611, USA
| | - Mustafa O. Guler
- The Institute for Bionanotechnology in Medicine (IBNAM), Northwestern University, Chicago, IL 60611, USA
- Institute of Materials Science and Nanotechnology, National Nanotechnology Research Center (UNAM), Bilkent University, Ankara, 06800, Turkey
| | - Matthew J. Webber
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Eugene T. Pashuck
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
| | - Masao Ito
- Laboratory for Memory and Learning, RIKEN Brain Science Institute, Wako-shi, 351-0198 Saitama, Japan
| | - Samuel I. Stupp
- The Institute for Bionanotechnology in Medicine (IBNAM), Northwestern University, Chicago, IL 60611, USA
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Biomedical Engineering, Northwestern University, Evanston, IL 60208, USA
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Thomas Launey
- Laboratory for Memory and Learning, RIKEN Brain Science Institute, Wako-shi, 351-0198 Saitama, Japan
- Launey Research Unit for Molecular Neurocybernetics, RIKEN Brain Science Institute, Wako-shi, 351-0198 Saitama, Japan
| |
Collapse
|
41
|
Chopra A, Murray ME, Byfield FJ, Mendez MG, Halleluyan R, Restle DJ, Raz-Ben Aroush D, Galie PA, Pogoda K, Bucki R, Marcinkiewicz C, Prestwich GD, Zarembinski TI, Chen CS, Puré E, Kresh JY, Janmey PA. Augmentation of integrin-mediated mechanotransduction by hyaluronic acid. Biomaterials 2014; 35:71-82. [PMID: 24120037 PMCID: PMC3930571 DOI: 10.1016/j.biomaterials.2013.09.066] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 09/20/2013] [Indexed: 12/26/2022]
Abstract
Changes in tissue and organ stiffness occur during development and are frequently symptoms of disease. Many cell types respond to the stiffness of substrates and neighboring cells in vitro and most cell types increase adherent area on stiffer substrates that are coated with ligands for integrins or cadherins. In vivo cells engage their extracellular matrix (ECM) by multiple mechanosensitive adhesion complexes and other surface receptors that potentially modify the mechanical signals transduced at the cell/ECM interface. Here we show that hyaluronic acid (also called hyaluronan or HA), a soft polymeric glycosaminoglycan matrix component prominent in embryonic tissue and upregulated during multiple pathologic states, augments or overrides mechanical signaling by some classes of integrins to produce a cellular phenotype otherwise observed only on very rigid substrates. The spread morphology of cells on soft HA-fibronectin coated substrates, characterized by formation of large actin bundles resembling stress fibers and large focal adhesions resembles that of cells on rigid substrates, but is activated by different signals and does not require or cause activation of the transcriptional regulator YAP. The fact that HA production is tightly regulated during development and injury and frequently upregulated in cancers characterized by uncontrolled growth and cell movement suggests that the interaction of signaling between HA receptors and specific integrins might be an important element in mechanical control of development and homeostasis.
Collapse
Affiliation(s)
- Anant Chopra
- Dept. of Cardiothoracic Surgery, Drexel Univ. College of Med, Philadelphia, PA, USA; Dept. of Bioengineering, Univ. of Pennsylvania, Philadelphia, PA, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Janmey PA, Wells RG, Assoian RK, McCulloch CA. From tissue mechanics to transcription factors. Differentiation 2013; 86:112-20. [PMID: 23969122 PMCID: PMC4545622 DOI: 10.1016/j.diff.2013.07.004] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 07/09/2013] [Accepted: 07/23/2013] [Indexed: 02/08/2023]
Abstract
Changes in tissue stiffness are frequently associated with diseases such as cancer, fibrosis, and atherosclerosis. Several recent studies suggest that, in addition to resulting from pathology, mechanical changes may play a role akin to soluble factors in causing the progression of disease, and similar mechanical control might be essential for normal tissue development and homeostasis. Many cell types alter their structure and function in response to exogenous forces or as a function of the mechanical properties of the materials to which they adhere. This review summarizes recent progress in identifying intracellular signaling pathways, and especially transcriptional programs, that are differentially activated when cells adhere to materials with different mechanical properties or when they are subject to tension arising from external forces. Several cytoplasmic or cytoskeletal signaling pathways involving small GTPases, focal adhesion kinase and transforming growth factor beta as well as the transcriptional regulators MRTF-A, NFκB, and Yap/Taz have emerged as important mediators of mechanical signaling.
Collapse
Affiliation(s)
- Paul A Janmey
- Departments of Physiology and Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | | | | | | |
Collapse
|
43
|
Sur S, Newcomb CJ, Webber MJ, Stupp SI. Tuning supramolecular mechanics to guide neuron development. Biomaterials 2013; 34:4749-57. [PMID: 23562052 PMCID: PMC3635952 DOI: 10.1016/j.biomaterials.2013.03.025] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 03/10/2013] [Indexed: 12/30/2022]
Abstract
The mechanical properties of the extracellular matrix (ECM) are known to influence neuronal differentiation and maturation, though the mechanism by which neuronal cells respond to these biophysical cues is not completely understood. Here we design ECM mimics using self-assembled peptide nanofibers, in which fiber rigidity is tailored by supramolecular interactions, in order to investigate the relationship between matrix stiffness and morphological development of hippocampal neurons. We observe that development of neuronal polarity is accelerated on soft nanofiber substrates, and results from the dynamics of neuronal processes. While the total neurite outgrowth of non-polar neurons remains conserved, weaker adhesion of neurites to soft PA substrate facilitates easier retraction, thus enhancing the frequency of "extension-retraction" events. We hypothesize that higher neurite motility enhances the probability of one neurite to reach a critical length relative to others, thereby initiating the developmental sequence of axon differentiation. Our results suggest that substrate stiffness can influence neuronal development by regulating its dynamics, thus providing useful information on scaffold design for applications in neural regeneration.
Collapse
Affiliation(s)
- Shantanu Sur
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, IL, 60611
| | - Christina J. Newcomb
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208
| | - Matthew J. Webber
- Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208
| | - Samuel I. Stupp
- The Institute for BioNanotechnology in Medicine, Northwestern University, Chicago, IL, 60611
- Department of Materials Science and Engineering, Northwestern University, Evanston, IL, 60208
- Department of Chemistry, Northwestern University, Evanston, IL, 60208
- Department of Medicine, Northwestern University, Chicago, IL, 60611
| |
Collapse
|
44
|
Abstract
Biological cells are well known to respond to a multitude of chemical signals. In the nervous system, chemical signaling has been shown to be crucially involved in development, normal functioning, and disorders of neurons and glial cells. However, there are an increasing number of studies showing that these cells also respond to mechanical cues. Here, we summarize current knowledge about the mechanical properties of nervous tissue and its building blocks, review recent progress in methodology and understanding of cellular mechanosensitivity in the nervous system, and provide an outlook on the implications of neuromechanics for future developments in biomedical engineering to aid overcoming some of the most devastating and currently incurable CNS pathologies such as spinal cord injuries and multiple sclerosis.
Collapse
Affiliation(s)
- Kristian Franze
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK.
| | | | | |
Collapse
|
45
|
Mechanosensitive TRPC1 channels promote calpain proteolysis of talin to regulate spinal axon outgrowth. J Neurosci 2013; 33:273-85. [PMID: 23283340 DOI: 10.1523/jneurosci.2142-12.2013] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Intracellular Ca(2+) signals control the development and regeneration of spinal axons downstream of chemical guidance cues, but little is known about the roles of mechanical cues in axon guidance. Here we show that transient receptor potential canonical 1 (TRPC1) subunits assemble mechanosensitive (MS) channels on Xenopus neuronal growth cones that regulate the extension and direction of axon outgrowth on rigid, but not compliant, substrata. Reducing expression of TRPC1 by antisense morpholinos inhibits the effects of MS channel blockers on axon outgrowth and local Ca(2+) transients. Ca(2+) influx through MS TRPC1 activates the protease calpain, which cleaves the integrin adaptor protein talin to reduce Src-dependent axon outgrowth, likely through altered adhesion turnover. We found that talin accumulates at the tips of dynamic filopodia, which is lost upon cleavage of talin by active calpain. This pathway may also be important in axon guidance decisions since asymmetric inhibition of MS TRPC1 is sufficient to induce growth cone turning. Together our results suggest that Ca(2+) influx through MS TRPC1 on filopodia activates calpain to control growth cone turning during development.
Collapse
|
46
|
Abstract
All cells are influenced by mechanical forces. In the brain, force-generating and load-bearing proteins twist, turn, ratchet, flex, compress, expand and bend to mediate neuronal signalling and plasticity. Although the functions of mechanosensitive proteins have been thoroughly described in classical sensory systems, the effects of endogenous mechanical energy on cellular function in the brain have received less attention, and many working models in neuroscience do not currently integrate principles of cellular mechanics. An understanding of cellular-mechanical concepts is essential to allow the integration of mechanobiology into ongoing studies of brain structure and function.
Collapse
|
47
|
Moore SW, Sheetz MP. Biophysics of substrate interaction: influence on neural motility, differentiation, and repair. Dev Neurobiol 2012; 71:1090-101. [PMID: 21739614 DOI: 10.1002/dneu.20947] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The identity and behavior of a cell is shaped by the molecular and mechanical composition of its surroundings. Molecular cues have firmly established roles in guiding both neuronal fate decisions and the migration of cells and axons. However, there is growing evidence that topographical and rigidity cues in the extracellular environment act synergistically with these molecular cues. Like chemical cues, physical factors do not elicit a fixed response, but rather one that depends on the sensory makeup of the cell. Moreover, from developmental studies and the plasticity of neural tissue, it is evident that there is dynamic feedback between physical and chemical factors to produce the final morphology. Here, we focus on our current understanding of how these physical cues shape cellular differentiation and migration, and discuss their relevance to repairing the injured nervous system.
Collapse
Affiliation(s)
- Simon W Moore
- Department of Biological Sciences, Columbia University, Sherman Fairchild Center, Amsterdam Ave., New York, NY 10027, USA.
| | | |
Collapse
|
48
|
Li X, Katsanevakis E, Liu X, Zhang N, Wen X. Engineering neural stem cell fates with hydrogel design for central nervous system regeneration. Prog Polym Sci 2012. [DOI: 10.1016/j.progpolymsci.2012.02.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
49
|
Protein tyrosine phosphatase α phosphotyrosyl-789 binds BCAR3 to position Cas for activation at integrin-mediated focal adhesions. Mol Cell Biol 2012; 32:3776-89. [PMID: 22801373 DOI: 10.1128/mcb.00214-12] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Integrin-mediated focal adhesions connect the extracellular matrix and cytoskeleton to regulate cell responses, such as migration. Protein tyrosine phosphatase α (PTPα) regulates integrin signaling, focal adhesion formation, and migration, but its roles in these events are incompletely understood. The integrin-proximal action of PTPα activates Src family kinases, and subsequent phosphorylation of PTPα at Tyr789 acts in an unknown manner to promote migration. PTPα-null cells were used in reconstitution assays to distinguish PTPα-Tyr789-dependent signaling events. This showed that PTPα-Tyr789 regulates the localization of PTPα and the scaffolding protein Cas to adhesion sites where Cas interacts with and is phosphorylated by Src to initiate Cas signaling. Linking these events, we identify BCAR3 as a molecular connector of PTPα and Cas, with phospho-Tyr789 PTPα serving as the first defined cellular ligand for the BCAR3 SH2 domain that recruits BCAR3-Cas to adhesions. Our findings reveal a novel role of PTPα in integrin-induced adhesion assembly that enables Src-mediated activation of the pivotal function of Cas in migration.
Collapse
|
50
|
Cells test substrate rigidity by local contractions on submicrometer pillars. Proc Natl Acad Sci U S A 2012; 109:5328-33. [PMID: 22431603 DOI: 10.1073/pnas.1119886109] [Citation(s) in RCA: 165] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Cell growth and differentiation are critically dependent upon matrix rigidity, yet many aspects of the cellular rigidity-sensing mechanism are not understood. Here, we analyze matrix forces after initial cell-matrix contact, when early rigidity-sensing events occur, using a series of elastomeric pillar arrays with dimensions extending to the submicron scale (2, 1, and 0.5 μm in diameter covering a range of stiffnesses). We observe that the cellular response is fundamentally different on micron-scale and submicron pillars. On 2-μm diameter pillars, adhesions form at the pillar periphery, forces are directed toward the center of the cell, and a constant maximum force is applied independent of stiffness. On 0.5-μm diameter pillars, adhesions form on the pillar tops, and local contractions between neighboring pillars are observed with a maximum displacement of ∼60 nm, independent of stiffness. Because mutants in rigidity sensing show no detectable displacement on 0.5-μm diameter pillars, there is a correlation between local contractions to 60 nm and rigidity sensing. Localization of myosin between submicron pillars demonstrates that submicron scale myosin filaments can cause these local contractions. Finally, submicron pillars can capture many details of cellular force generation that are missed on larger pillars and more closely mimic continuous surfaces.
Collapse
|