1
|
Hartman S, Ryan SD, Karamched BR. Walk this way: modeling foraging ant dynamics in multiple food source environments. J Math Biol 2024; 89:41. [PMID: 39266783 PMCID: PMC11392994 DOI: 10.1007/s00285-024-02136-2] [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: 01/18/2024] [Revised: 06/14/2024] [Accepted: 08/08/2024] [Indexed: 09/14/2024]
Abstract
Foraging for resources is an essential process for the daily life of an ant colony. What makes this process so fascinating is the self-organization of ants into trails using chemical pheromone in the absence of direct communication. Here we present a stochastic lattice model that captures essential features of foraging ant dynamics inspired by recent agent-based models while forgoing more detailed interactions that may not be essential to trail formation. Nevertheless, our model's results coincide with those presented in more sophisticated theoretical models and experiments. Furthermore, it captures the phenomenon of multiple trail formation in environments with multiple food sources. This latter phenomenon is not described well by other more detailed models. We complement the stochastic lattice model by describing a macroscopic PDE which captures the basic structure of lattice model. The PDE provides a continuum framework for the first-principle interactions described in the stochastic lattice model and is amenable to analysis. Linear stability analysis of this PDE facilitates a computational study of the impact various parameters impart on trail formation. We also highlight universal features of the modeling framework that may allow this simple formation to be used to study complex systems beyond ants.
Collapse
Affiliation(s)
- Sean Hartman
- College of Music, Florida State University, Tallahassee, FL, 32306, USA
- Department of Mathematics, Florida State University, Tallahassee, FL, 32306, USA
| | - Shawn D Ryan
- Department of Mathematics and Statistics, Cleveland State University, Cleveland, OH, 44115, USA.
- Center for Applied Data Analysis and Modeling, Cleveland State University, Cleveland, 44115, OH, USA.
| | - Bhargav R Karamched
- Department of Mathematics, Florida State University, Tallahassee, FL, 32306, USA.
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, 32306, USA.
- Program in Neuroscience, Florida State University, Tallahassee, FL, 32306, USA.
| |
Collapse
|
2
|
Di Meo D, Kundu T, Ravindran P, Shah B, Püschel AW. Pip5k1γ regulates axon formation by limiting Rap1 activity. Life Sci Alliance 2024; 7:e202302383. [PMID: 38438249 PMCID: PMC10912816 DOI: 10.26508/lsa.202302383] [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: 09/19/2023] [Revised: 02/26/2024] [Accepted: 02/26/2024] [Indexed: 03/06/2024] Open
Abstract
During their differentiation, neurons establish a highly polarized morphology by forming axons and dendrites. Cortical and hippocampal neurons initially extend several short neurites that all have the potential to become an axon. One of these neurites is then selected as the axon by a combination of positive and negative feedback signals that promote axon formation and prevent the remaining neurites from developing into axons. Here, we show that Pip5k1γ is required for the formation of a single axon as a negative feedback signal that regulates C3G and Rap1 through the generation of phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2). Impairing the function of Pip5k1γ results in a hyper-activation of the Fyn/C3G/Rap1 pathway, which induces the formation of supernumerary axons. Application of a hyper-osmotic shock to modulate membrane tension has a similar effect, increasing Rap1 activity and inducing the formation of supernumerary axons. In both cases, the induction of supernumerary axons can be reverted by expressing constitutively active Pip5k. Our results show that PI(4,5)P2-dependent membrane properties limit the activity of C3G and Rap1 to ensure the extension of a single axon.
Collapse
Affiliation(s)
- Danila Di Meo
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
- https://ror.org/00pd74e08 Cells-in-Motion Interfaculty Center, University of Münster, Münster, Germany
| | - Trisha Kundu
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
- https://ror.org/00pd74e08 Cells-in-Motion Interfaculty Center, University of Münster, Münster, Germany
| | - Priyadarshini Ravindran
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
| | - Bhavin Shah
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
| | - Andreas W Püschel
- https://ror.org/00pd74e08 Institut für Integrative Zellbiologie und Physiologie, Universität Münster, Münster, Germany
- https://ror.org/00pd74e08 Cells-in-Motion Interfaculty Center, University of Münster, Münster, Germany
| |
Collapse
|
3
|
Staii C. Nonlinear Growth Dynamics of Neuronal Cells Cultured on Directional Surfaces. Biomimetics (Basel) 2024; 9:203. [PMID: 38667214 PMCID: PMC11048115 DOI: 10.3390/biomimetics9040203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/20/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024] Open
Abstract
During the development of the nervous system, neuronal cells extend axons and dendrites that form complex neuronal networks, which are essential for transmitting and processing information. Understanding the physical processes that underlie the formation of neuronal networks is essential for gaining a deeper insight into higher-order brain functions such as sensory processing, learning, and memory. In the process of creating networks, axons travel towards other recipient neurons, directed by a combination of internal and external cues that include genetic instructions, biochemical signals, as well as external mechanical and geometrical stimuli. Although there have been significant recent advances, the basic principles governing axonal growth, collective dynamics, and the development of neuronal networks remain poorly understood. In this paper, we present a detailed analysis of nonlinear dynamics for axonal growth on surfaces with periodic geometrical patterns. We show that axonal growth on these surfaces is described by nonlinear Langevin equations with speed-dependent deterministic terms and gaussian stochastic noise. This theoretical model yields a comprehensive description of axonal growth at both intermediate and long time scales (tens of hours after cell plating), and predicts key dynamical parameters, such as speed and angular correlation functions, axonal mean squared lengths, and diffusion (cell motility) coefficients. We use this model to perform simulations of axonal trajectories on the growth surfaces, in turn demonstrating very good agreement between simulated growth and the experimental results. These results provide important insights into the current understanding of the dynamical behavior of neurons, the self-wiring of the nervous system, as well as for designing innovative biomimetic neural network models.
Collapse
Affiliation(s)
- Cristian Staii
- Department of Physics and Astronomy, Tufts University, Medford, MA 02155, USA
| |
Collapse
|
4
|
Xu Z, Angstmann CN, Wu Y, Stefen H, Parić E, Fath T, Curmi PM. Location of the axon initial segment assembly can be predicted from neuronal shape. iScience 2024; 27:109264. [PMID: 38450155 PMCID: PMC10915628 DOI: 10.1016/j.isci.2024.109264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/21/2023] [Accepted: 02/14/2024] [Indexed: 03/08/2024] Open
Abstract
The axon initial segment (AIS) is located at the proximal axon demarcating the boundary between axonal and somatodendritic compartments. The AIS facilitates the generation of action potentials and maintenance of neuronal polarity. In this study, we show that the location of AIS assembly, as marked by Ankyrin G, corresponds to the nodal plane of the lowest-order harmonic of the Laplace-Beltrami operator solved over the neuronal shape. This correlation establishes a coupling between location of AIS assembly and neuronal cell morphology. We validate this correlation for neurons with atypical morphology and neurons containing multiple AnkG clusters on distinct neurites, where the nodal plane selects the appropriate axon showing enriched Tau. Based on our findings, we propose that Turing patterning systems are candidates for dynamically governing AIS location. Overall, this study highlights the importance of neuronal cell morphology in determining the precise localization of the AIS within the proximal axon.
Collapse
Affiliation(s)
- Zhuang Xu
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW 2052, Australia
- School of Mathematics and Statistics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Christopher N. Angstmann
- School of Mathematics and Statistics, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Yuhuang Wu
- Infection Analytics Program, Kirby Institute for Infection and Immunity, The University of New South Wales, Sydney, NSW 2052, Australia
| | - Holly Stefen
- Dementia Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Esmeralda Parić
- Dementia Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Thomas Fath
- Dementia Research Centre, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW 2109, Australia
| | - Paul M.G. Curmi
- School of Physics, The University of New South Wales, Sydney, NSW 2052, Australia
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW 2052, Australia
| |
Collapse
|
5
|
Qiu Z, Minegishi T, Aoki D, Abe K, Baba K, Inagaki N. Adhesion-clutch between DCC and netrin-1 mediates netrin-1-induced axonal haptotaxis. Front Mol Neurosci 2024; 17:1307755. [PMID: 38375502 PMCID: PMC10875621 DOI: 10.3389/fnmol.2024.1307755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 01/08/2024] [Indexed: 02/21/2024] Open
Abstract
The growth cone, a motile structure located at the tip of growing axons, senses extracellular guidance cues and translates them into directional forces that drive axon outgrowth and guidance. Axon guidance directed by chemical cues on the extracellular adhesive substrate is termed haptotaxis. Recent studies reported that netrin-1 on the substrate functions as a haptotactic axon guidance cue. However, the mechanism mediating netrin-1-induced axonal haptotaxis remains unclear. Here, we demonstrate that substrate-bound netrin-1 induces axonal haptotaxis by facilitating physical interactions between the netrin-1 receptor, DCC, and the adhesive substrates. DCC serves as an adhesion receptor for netrin-1. The clutch-linker molecule shootin1a interacted with DCC, linking it to actin filament retrograde flow at the growth cone. Speckle imaging analyses showed that DCC underwent either grip (stop) or retrograde slip on the adhesive substrate. The grip state was more prevalent on netrin-1-coated substrate compared to the control substrate polylysine, thereby transmitting larger traction force on the netrin-1-coated substrate. Furthermore, disruption of the linkage between actin filament retrograde flow and DCC by shootin1 knockout impaired netrin-1-induced axonal haptotaxis. These results suggest that the directional force for netrin-1-induced haptotaxis is exerted on the substrates through the adhesion-clutch between DCC and netrin-1 which occurs asymmetrically within the growth cone.
Collapse
Affiliation(s)
| | | | | | | | | | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Nara, Japan
| |
Collapse
|
6
|
Bai F, Bertram R, Karamched BR. A mathematical study of the efficacy of possible negative feedback pathways involved in neuronal polarization. J Theor Biol 2023; 571:111561. [PMID: 37331648 DOI: 10.1016/j.jtbi.2023.111561] [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: 03/01/2023] [Revised: 05/29/2023] [Accepted: 06/11/2023] [Indexed: 06/20/2023]
Abstract
Neuronal polarization, a process wherein nascent neurons develop a single long axon and multiple short dendrites, can occur within in vitro cell cultures without environmental cues. This is an apparently random process in which one of several short processes, called neurites, grows to become long, while the others remain short. In this study, we propose a minimum model for neurite growth, which involves bistability and random excitations reflecting actin waves. Positive feedback is needed to produce the bistability, while negative feedback is required to ensure that no more than one neurite wins the winner-takes-all contest. By applying the negative feedback to different aspects of the neurite growth process, we demonstrate that targeting the negative feedback to the excitation amplitude results in the most persistent polarization. Also, we demonstrate that there are optimal ranges of values for the neurite count, and for the excitation rate and amplitude that best maintain the polarization. Finally, we show that a previously published model for neuronal polarization based on competition for limited resources shares key features with our best-performing minimal model: bistability and negative feedback targeted to the size of random excitations.
Collapse
Affiliation(s)
- Fan Bai
- Department of Mathematics, Florida State University, Tallahassee FL 32306, United States
| | - Richard Bertram
- Department of Mathematics, Florida State University, Tallahassee FL 32306, United States; Program in Molecular Biophysics, Florida State University, Tallahassee FL 32306, United States; Program in Neuroscience, Florida State University, Tallahassee FL 32306, United States
| | - Bhargav R Karamched
- Department of Mathematics, Florida State University, Tallahassee FL 32306, United States; Program in Molecular Biophysics, Florida State University, Tallahassee FL 32306, United States; Program in Neuroscience, Florida State University, Tallahassee FL 32306, United States.
| |
Collapse
|
7
|
Kunida K, Takagi N, Aoki K, Ikeda K, Nakamura T, Sakumura Y. Decoding cellular deformation from pseudo-simultaneously observed Rho GTPase activities. Cell Rep 2023; 42:112071. [PMID: 36764299 DOI: 10.1016/j.celrep.2023.112071] [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: 10/17/2022] [Revised: 10/31/2022] [Accepted: 01/19/2023] [Indexed: 02/11/2023] Open
Abstract
Limitations in simultaneously observing the activity of multiple molecules in live cells prevent researchers from elucidating how these molecules coordinate the dynamic regulation of cellular functions. Here, we propose the motion-triggered average (MTA) algorithm to characterize pseudo-simultaneous dynamic changes in arbitrary cellular deformation and molecular activities. Using MTA, we successfully extract a pseudo-simultaneous time series from individually observed activities of three Rho GTPases: Cdc42, Rac1, and RhoA. To verify that this time series encoded information on cell-edge movement, we use a mathematical regression model to predict the edge velocity from the activities of the three molecules. The model accurately predicts the unknown edge velocity, providing numerical evidence that these Rho GTPases regulate edge movement. Data preprocessing using MTA combined with mathematical regression provides an effective strategy for reusing numerous individual observations of molecular activities.
Collapse
Affiliation(s)
- Katsuyuki Kunida
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara 8916-5, Japan; School of Medicine, Fujita Health University, Toyoake, Aichi 470-1192, Japan
| | - Nobuhiro Takagi
- Graduate School of Information Science and Technology, Aichi Prefectural University, Nagakute, Aichi 480-1342, Japan
| | - Kazuhiro Aoki
- National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Exploratory Research Center on Life and Living Systems (ExCELLS), National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan; Department of Basic Biology, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan
| | - Kazushi Ikeda
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara 8916-5, Japan; Data Science Center, Nara Institute of Science and Technology, Ikoma, Nara 8916-5, Japan; RIKEN Center for Advanced Intelligence Project (RIKEN AIP), Kyoto 619-0288, Japan
| | - Takeshi Nakamura
- Research Institute for Biomedical Sciences, Tokyo University of Science, Noda, Chiba 278-0022, Japan
| | - Yuichi Sakumura
- Graduate School of Science and Technology, Nara Institute of Science and Technology, Ikoma, Nara 8916-5, Japan; Data Science Center, Nara Institute of Science and Technology, Ikoma, Nara 8916-5, Japan.
| |
Collapse
|
8
|
Burute M, Jansen KI, Mihajlovic M, Vermonden T, Kapitein LC. Local changes in microtubule network mobility instruct neuronal polarization and axon specification. SCIENCE ADVANCES 2022; 8:eabo2343. [PMID: 36332030 PMCID: PMC9635826 DOI: 10.1126/sciadv.abo2343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
The polarization of neurons into axons and dendrites depends on extracellular cues, intracellular signaling, cytoskeletal rearrangements, and polarized transport, but the interplay between these processes during polarization remains unresolved. Here, we show that axon specification is determined by differences in microtubule network mobility between neurites, regulated by Rho guanosine triphosphatases (GTPases) and extracellular cues. In developing neurons, retrograde microtubule flow prevents the entry of the axon-selective motor protein Kinesin-1 into most neurites. Using inducible assays to control microtubule network flow, we demonstrate that local inhibition of microtubule mobility is sufficient to guide Kinesin-1 into a specific neurite, whereas long-term global inhibition induces the formation of multiple axons. We furthermore show that extracellular mechanical cues and intracellular Rho GTPase signaling control the local differences in microtubule network flow. These results reveal a novel cytoskeletal mechanism for neuronal polarization.
Collapse
Affiliation(s)
- Mithila Burute
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, Netherlands
| | - Klara I. Jansen
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, Netherlands
| | - Marko Mihajlovic
- Department of Pharmaceutical Sciences, Utrecht Institute for Pharmaceutical Sciences (UIPS), Science for Life, Utrecht University, Universiteitsweg 99, 3508 TB Utrecht, Netherlands
| | - Tina Vermonden
- Department of Pharmaceutical Sciences, Utrecht Institute for Pharmaceutical Sciences (UIPS), Science for Life, Utrecht University, Universiteitsweg 99, 3508 TB Utrecht, Netherlands
| | - Lukas C. Kapitein
- Cell Biology, Neurobiology and Biophysics, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, Netherlands
| |
Collapse
|
9
|
Guo CL. Self-Sustained Regulation or Self-Perpetuating Dysregulation: ROS-dependent HIF-YAP-Notch Signaling as a Double-Edged Sword on Stem Cell Physiology and Tumorigenesis. Front Cell Dev Biol 2022; 10:862791. [PMID: 35774228 PMCID: PMC9237464 DOI: 10.3389/fcell.2022.862791] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 04/29/2022] [Indexed: 12/19/2022] Open
Abstract
Organ development, homeostasis, and repair often rely on bidirectional, self-organized cell-niche interactions, through which cells select cell fate, such as stem cell self-renewal and differentiation. The niche contains multiplexed chemical and mechanical factors. How cells interpret niche structural information such as the 3D topology of organs and integrate with multiplexed mechano-chemical signals is an open and active research field. Among all the niche factors, reactive oxygen species (ROS) have recently gained growing interest. Once considered harmful, ROS are now recognized as an important niche factor in the regulation of tissue mechanics and topology through, for example, the HIF-YAP-Notch signaling pathways. These pathways are not only involved in the regulation of stem cell physiology but also associated with inflammation, neurological disorder, aging, tumorigenesis, and the regulation of the immune checkpoint molecule PD-L1. Positive feedback circuits have been identified in the interplay of ROS and HIF-YAP-Notch signaling, leading to the possibility that under aberrant conditions, self-organized, ROS-dependent physiological regulations can be switched to self-perpetuating dysregulation, making ROS a double-edged sword at the interface of stem cell physiology and tumorigenesis. In this review, we discuss the recent findings on how ROS and tissue mechanics affect YAP-HIF-Notch-PD-L1 signaling, hoping that the knowledge can be used to design strategies for stem cell-based and ROS-targeting therapy and tissue engineering.
Collapse
Affiliation(s)
- Chin-Lin Guo
- Institute of Physics, Academia Sinica, Taipei, Taiwan
| |
Collapse
|
10
|
Abstract
The establishment of a functioning neuronal network is a crucial step in neural development. During this process, neurons extend neurites-axons and dendrites-to meet other neurons and interconnect. Therefore, these neurites need to migrate, grow, branch and find the correct path to their target by processing sensory cues from their environment. These processes rely on many coupled biophysical effects including elasticity, viscosity, growth, active forces, chemical signaling, adhesion and cellular transport. Mathematical models offer a direct way to test hypotheses and understand the underlying mechanisms responsible for neuron development. Here, we critically review the main models of neurite growth and morphogenesis from a mathematical viewpoint. We present different models for growth, guidance and morphogenesis, with a particular emphasis on mechanics and mechanisms, and on simple mathematical models that can be partially treated analytically.
Collapse
Affiliation(s)
- Hadrien Oliveri
- Mathematical Institute, University of Oxford, Oxford, OX2 6GG, UK
| | - Alain Goriely
- Mathematical Institute, University of Oxford, Oxford, OX2 6GG, UK.
| |
Collapse
|
11
|
A closed-loop multi-scale model for intrinsic frequency-dependent regulation of axonal growth. Math Biosci 2021; 344:108768. [PMID: 34952037 DOI: 10.1016/j.mbs.2021.108768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 12/10/2021] [Accepted: 12/15/2021] [Indexed: 11/22/2022]
Abstract
This article develops a closed-loop multi-scale model for axon length regulation based on a frequency-dependent negative feedback mechanism. It builds on earlier models by linking molecular motor dynamics to signaling delays that then determine signal oscillation period. The signal oscillation is treated as a front end for a signaling pathway that modulates axonal length. This model is used to demonstrate the feasibility of such a mechanism and is tested against two previously published reports in which experimental manipulations were performed that resulted in axon growth. The model captures these observations and yields an expression for equilibrium axonal length. One major prediction of the model is that increasing motor density in the body of an axon results in axonal growth-this idea has not yet been explored experimentally.
Collapse
|
12
|
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
|
13
|
Humpert I, Di Meo D, Püschel AW, Pietschmann JF. On the role of vesicle transport in neurite growth: Modeling and experiments. Math Biosci 2021; 338:108632. [PMID: 34087317 DOI: 10.1016/j.mbs.2021.108632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 04/28/2021] [Accepted: 05/17/2021] [Indexed: 10/21/2022]
Abstract
The processes that determine the establishment of the complex morphology of neurons during development are still poorly understood. Here, we focus on the question how a difference in the length of neurites affects vesicle transport. We performed live imaging experiments and present a lattice-based model to gain a deeper theoretical understanding of intracellular transport in neurons. After a motivation and appropriate scaling of the model we present numerical simulations showing that initial differences in neurite length result in phenomena of biological relevance, i.e. a positive feedback that enhances transport into the longer neurite and oscillation of vesicles concentrations that can be interpreted as cycles of extension and retraction observed in experiments. Thus, our model is a first step towards a better understanding of the interplay between the transport of vesicles and the spatial organization of cells.
Collapse
Affiliation(s)
- Ina Humpert
- Applied Mathematics Münster: Institute for Analysis and Computational Mathematics, Westfälische Wilhelms-Universität (WWU) Münster, Germany.
| | - Danila Di Meo
- Institute for Molecular Biology, Westfälische-Wilhelms-Universität (WWU) Münster, Germany.
| | - Andreas W Püschel
- Institute for Molecular Biology, Westfälische-Wilhelms-Universität (WWU) Münster, Germany.
| | | |
Collapse
|
14
|
Engel KL, Arora A, Goering R, Lo HYG, Taliaferro JM. Mechanisms and consequences of subcellular RNA localization across diverse cell types. Traffic 2020; 21:404-418. [PMID: 32291836 PMCID: PMC7304542 DOI: 10.1111/tra.12730] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 03/26/2020] [Accepted: 03/30/2020] [Indexed: 02/07/2023]
Abstract
Essentially all cells contain a variety of spatially restricted regions that are important for carrying out specialized functions. Often, these regions contain specialized transcriptomes that facilitate these functions by providing transcripts for localized translation. These transcripts play a functional role in maintaining cell physiology by enabling a quick response to changes in the cellular environment. Here, we review how RNA molecules are trafficked within cells, with a focus on the subcellular locations to which they are trafficked, mechanisms that regulate their transport and clinical disorders associated with misregulation of the process.
Collapse
Affiliation(s)
- Krysta L Engel
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Ankita Arora
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Raeann Goering
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Hei-Yong G Lo
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - J Matthew Taliaferro
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
- RNA Bioscience Initiative, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| |
Collapse
|
15
|
Abstract
Individual cell types have characteristic sizes, suggesting that size sensing mechanisms may coordinate transcription, translation, and metabolism with cell growth rates. Two types of size-sensing mechanisms have been proposed: spatial sensing of the location or dimensions of a signal, subcellular structure or organelle; or titration-based sensing of the intracellular concentrations of key regulators. Here we propose that size sensing in animal cells combines both titration and spatial sensing elements in a dynamic mechanism whereby microtubule motor-dependent localization of RNA encoding importin β1 and mTOR, coupled with regulated local protein synthesis, enable cytoskeleton length sensing for cell growth regulation.
Collapse
Affiliation(s)
- Ida Rishal
- Department of Biomolecular Sciences, Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Mike Fainzilber
- Department of Biomolecular Sciences, Weizmann Institute of Science, 76100, Rehovot, Israel.
| |
Collapse
|
16
|
Takano T, Funahashi Y, Kaibuchi K. Neuronal Polarity: Positive and Negative Feedback Signals. Front Cell Dev Biol 2019; 7:69. [PMID: 31069225 PMCID: PMC6491837 DOI: 10.3389/fcell.2019.00069] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 04/09/2019] [Indexed: 12/21/2022] Open
Abstract
Establishment and maintenance of neuronal polarity are critical for neuronal development and function. One of the fundamental questions in neurodevelopment is how neurons generate only one axon and several dendrites from multiple minor neurites. Over the past few decades, molecular and cell biological approaches have unveiled a large number of signaling networks regulating neuronal polarity in cultured hippocampal neurons and the developing cortex. Emerging evidence reveals that positive and negative feedback signals play a crucial role in axon and dendrite specification. Positive feedback signals are continuously activated in one of minor neurites and result in axon specification and elongation, whereas negative feedback signals are propagated from a nascent axon terminal to all minor neurites and inhibit the formation of multiple axon, thereby leading to dendrite specification, and maintaining neuronal polarity. This current insight provides a holistic picture of the signaling mechanisms underlying neuronal polarization during neuronal development. Here, our review highlights recent advancements in this fascinating field, with a focus on the positive, and negative feedback signals as key regulatory mechanisms underlying neuronal polarization.
Collapse
Affiliation(s)
- Tetsuya Takano
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan.,Department of Cell Biology, Duke University Medical School, Durham, NC, United States
| | - Yasuhiro Funahashi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kozo Kaibuchi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| |
Collapse
|
17
|
Padmanabhan P, Goodhill GJ. Axon growth regulation by a bistable molecular switch. Proc Biol Sci 2019; 285:rspb.2017.2618. [PMID: 29669897 DOI: 10.1098/rspb.2017.2618] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 03/19/2018] [Indexed: 02/07/2023] Open
Abstract
For the brain to function properly, its neurons must make the right connections during neural development. A key aspect of this process is the tight regulation of axon growth as axons navigate towards their targets. Neuronal growth cones at the tips of developing axons switch between growth and paused states during axonal pathfinding, and this switching behaviour determines the heterogeneous axon growth rates observed during brain development. The mechanisms controlling this switching behaviour, however, remain largely unknown. Here, using mathematical modelling, we predict that the molecular interaction network involved in axon growth can exhibit bistability, with one state representing a fast-growing growth cone state and the other a paused growth cone state. Owing to stochastic effects, even in an unchanging environment, model growth cones reversibly switch between growth and paused states. Our model further predicts that environmental signals could regulate axon growth rate by controlling the rates of switching between the two states. Our study presents a new conceptual understanding of growth cone switching behaviour, and suggests that axon guidance may be controlled by both cell-extrinsic factors and cell-intrinsic growth regulatory mechanisms.
Collapse
Affiliation(s)
- Pranesh Padmanabhan
- Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| | - Geoffrey J Goodhill
- Queensland Brain Institute, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia .,School of Mathematics and Physics, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
| |
Collapse
|
18
|
Zhang Y, Nichols EL, Zellmer AM, Guldner IH, Kankel C, Zhang S, Howard SS, Smith CJ. Generating intravital super-resolution movies with conventional microscopy reveals actin dynamics that construct pioneer axons. Development 2019; 146:dev.171512. [PMID: 30760484 PMCID: PMC6432666 DOI: 10.1242/dev.171512] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/04/2019] [Indexed: 01/06/2023]
Abstract
Super-resolution microscopy is broadening our in-depth understanding of cellular structure. However, super-resolution approaches are limited, for numerous reasons, from utilization in longer-term intravital imaging. We devised a combinatorial imaging technique that combines deconvolution with stepwise optical saturation microscopy (DeSOS) to circumvent this issue and image cells in their native physiological environment. Other than a traditional confocal or two-photon microscope, this approach requires no additional hardware. Here, we provide an open-access application to obtain DeSOS images from conventional microscope images obtained at low excitation powers. We show that DeSOS can be used in time-lapse imaging to generate super-resolution movies in zebrafish. DeSOS was also validated in live mice. These movies uncover that actin structures dynamically remodel to produce a single pioneer axon in a ‘top-down’ scaffolding event. Further, we identify an F-actin population – stable base clusters – that orchestrate that scaffolding event. We then identify that activation of Rac1 in pioneer axons destabilizes stable base clusters and disrupts pioneer axon formation. The ease of acquisition and processing with this approach provides a universal technique for biologists to answer questions in living animals. Summary: Actin dynamics are examined in zebrafish axons using DeSOS, a new super-resolution technique combining deconvolution with stepwise optical saturation microscopy that allows detailed intravital imaging of cells in their native environments.
Collapse
Affiliation(s)
- Yide Zhang
- Department of Electrical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Evan L Nichols
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Abigail M Zellmer
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Ian H Guldner
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Mike and Josie Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556, USA.,Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, IN 46202, USA
| | - Cody Kankel
- Center for Research Computing. University of Notre Dame, Notre Dame, IN 46556, USA
| | - Siyuan Zhang
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.,Mike and Josie Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556, USA.,Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, IN 46202, USA
| | - Scott S Howard
- Department of Electrical Engineering, University of Notre Dame, Notre Dame, IN 46556, USA .,Mike and Josie Harper Cancer Research Institute, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Cody J Smith
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA .,Center for Stem Cells and Regenerative Medicine, University of Notre Dame, Notre Dame, IN 46556, USA
| |
Collapse
|
19
|
Goodhill GJ. Theoretical Models of Neural Development. iScience 2018; 8:183-199. [PMID: 30321813 PMCID: PMC6197653 DOI: 10.1016/j.isci.2018.09.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/06/2018] [Accepted: 09/19/2018] [Indexed: 12/22/2022] Open
Abstract
Constructing a functioning nervous system requires the precise orchestration of a vast array of mechanical, molecular, and neural-activity-dependent cues. Theoretical models can play a vital role in helping to frame quantitative issues, reveal mathematical commonalities between apparently diverse systems, identify what is and what is not possible in principle, and test the abilities of specific mechanisms to explain the data. This review focuses on the progress that has been made over the last decade in our theoretical understanding of neural development.
Collapse
Affiliation(s)
- Geoffrey J Goodhill
- Queensland Brain Institute and School of Mathematics and Physics, The University of Queensland, St Lucia, QLD 4072, Australia.
| |
Collapse
|
20
|
Hapak SM, Ghosh S, Rothlin CV. Axon Regeneration: Antagonistic Signaling Pairs in Neuronal Polarization. Trends Mol Med 2018; 24:615-629. [PMID: 29934283 DOI: 10.1016/j.molmed.2018.05.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/07/2018] [Accepted: 05/09/2018] [Indexed: 01/29/2023]
Abstract
Genome-wide screens, proteomics, and candidate-based approaches have identified numerous genes associated with neuronal regeneration following central nervous system (CNS) injury. Despite significant progress, functional recovery remains a challenge, even in model systems. Neuronal function depends on segregation of axonal versus dendritic domains. A key to functional recovery may lie in recapitulating the developmental signals that instruct axon specification and growth in adult neurons post-injury. Theoretically, binary activator-inhibitor elements operating as a Turing-like system within neurons can specify axonal versus dendritic domains and promote axon growth. We review here various molecules implicated in axon specification that function as signaling pairs driving neuronal polarization and axon growth.
Collapse
Affiliation(s)
- Sophie M Hapak
- Department of Medicine, School of Medicine, University of Minnesota, 401 East River Parkway, Minneapolis, MN 55455, USA
| | - Sourav Ghosh
- Department of Neurology, School of Medicine, Yale University, 300 George Street, New Haven, CT 06511, USA; Department of Pharmacology, School of Medicine, Yale University, 333 Cedar Street, New Haven, CT 06520, USA; Equal contribution.
| | - Carla V Rothlin
- Department of Pharmacology, School of Medicine, Yale University, 333 Cedar Street, New Haven, CT 06520, USA; Department of Immunobiology, School of Medicine, Yale University, 300 Cedar Street, New Haven, CT 06520, USA; Equal contribution.
| |
Collapse
|
21
|
Sapir T, Levy T, Kozer N, Shin I, Zamor V, Haffner-Krausz R, McGlade JC, Reiner O. Notch Activation by Shootin1 Opposing Activities on 2 Ubiquitin Ligases. Cereb Cortex 2017; 28:3115-3128. [DOI: 10.1093/cercor/bhx180] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 06/23/2017] [Indexed: 12/22/2022] Open
Affiliation(s)
- Tamar Sapir
- Department of Molecular Genetics, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| | - Talia Levy
- Department of Molecular Genetics, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| | - Noga Kozer
- Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| | - Irina Shin
- Biological Services Unit, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| | - Vanessa Zamor
- Department of Molecular Genetics, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| | - Rebecca Haffner-Krausz
- Department of Veterinary Resources, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| | - Jane C McGlade
- The Arthur and Sonia Labatt Brain Tumour Research Centre and Program in Cell Biology, The Hospital for Sick Children, 555 University Avenue, Toronto, ON,Canada
- Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON, Canada
| | - Orly Reiner
- Department of Molecular Genetics, Weizmann Institute of Science, 234 Herzl St., Rehovot, Israel
| |
Collapse
|
22
|
Actin Waves: Origin of Cell Polarization and Migration? Trends Cell Biol 2017; 27:515-526. [DOI: 10.1016/j.tcb.2017.02.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/26/2017] [Accepted: 02/07/2017] [Indexed: 01/22/2023]
|
23
|
Discovery of long-range inhibitory signaling to ensure single axon formation. Nat Commun 2017; 8:33. [PMID: 28652571 PMCID: PMC5484694 DOI: 10.1038/s41467-017-00044-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 04/27/2017] [Indexed: 01/12/2023] Open
Abstract
A long-standing question in neurodevelopment is how neurons develop a single axon and multiple dendrites from common immature neurites. Long-range inhibitory signaling from the growing axon is hypothesized to prevent outgrowth of other immature neurites and to differentiate them into dendrites, but the existence and nature of this inhibitory signaling remains unknown. Here, we demonstrate that axonal growth triggered by neurotrophin-3 remotely inhibits neurite outgrowth through long-range Ca2+ waves, which are delivered from the growing axon to the cell body. These Ca2+ waves increase RhoA activity in the cell body through calcium/calmodulin-dependent protein kinase I. Optogenetic control of Rho-kinase combined with computational modeling reveals that active Rho-kinase diffuses to growing other immature neurites and inhibits their outgrowth. Mechanistically, calmodulin-dependent protein kinase I phosphorylates a RhoA-specific GEF, GEF-H1, whose phosphorylation enhances its GEF activity. Thus, our results reveal that long-range inhibitory signaling mediated by Ca2+ wave is responsible for neuronal polarization. Emerging evidence suggests that gut microbiota influences immune function in the brain and may play a role in neurological diseases. Here, the authors offer in vivo evidence from a Drosophila model that supports a role for gut microbiota in modulating the progression of Alzheimer’s disease.
Collapse
|
24
|
Neuronal polarization: From spatiotemporal signaling to cytoskeletal dynamics. Mol Cell Neurosci 2017; 84:11-28. [PMID: 28363876 DOI: 10.1016/j.mcn.2017.03.008] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/24/2017] [Accepted: 03/26/2017] [Indexed: 12/20/2022] Open
Abstract
Neuronal polarization establishes distinct molecular structures to generate a single axon and multiple dendrites. Studies over the past years indicate that this efficient separation is brought about by a network of feedback loops. Axonal growth seems to play a major role in fueling those feedback loops and thereby stabilizing neuronal polarity. Indeed, various effectors involved in feedback loops are pivotal for axonal growth by ultimately acting on the actin and microtubule cytoskeleton. These effectors have key roles in interconnecting actin and microtubule dynamics - a mechanism crucial to commanding the growth of axons. We propose a model connecting signaling with cytoskeletal dynamics and neurite growth to better describe the underlying processes involved in neuronal polarization. We will discuss the current views on feedback loops and highlight the current limits of our understanding.
Collapse
|
25
|
Naoki H, Nishiyama M, Togashi K, Igarashi Y, Hong K, Ishii S. Multi-phasic bi-directional chemotactic responses of the growth cone. Sci Rep 2016; 6:36256. [PMID: 27808115 PMCID: PMC5093620 DOI: 10.1038/srep36256] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 10/12/2016] [Indexed: 11/23/2022] Open
Abstract
The nerve growth cone is bi-directionally attracted and repelled by the same cue molecules depending on the situations, while other non-neural chemotactic cells usually show uni-directional attraction or repulsion toward their specific cue molecules. However, how the growth cone differs from other non-neural cells remains unclear. Toward this question, we developed a theory for describing chemotactic response based on a mathematical model of intracellular signaling of activator and inhibitor. Our theory was first able to clarify the conditions of attraction and repulsion, which are determined by balance between activator and inhibitor, and the conditions of uni- and bi-directional responses, which are determined by dose-response profiles of activator and inhibitor to the guidance cue. With biologically realistic sigmoidal dose-responses, our model predicted tri-phasic turning response depending on intracellular Ca2+ level, which was then experimentally confirmed by growth cone turning assays and Ca2+ imaging. Furthermore, we took a reverse-engineering analysis to identify balanced regulation between CaMKII (activator) and PP1 (inhibitor) and then the model performance was validated by reproducing turning assays with inhibitions of CaMKII and PP1. Thus, our study implies that the balance between activator and inhibitor underlies the multi-phasic bi-directional turning response of the growth cone.
Collapse
Affiliation(s)
- Honda Naoki
- Graduate School of Medicine, Kyoto University, Sakyo, Kyoto, Japan.,Imaging Platform for Spatio-temporal Information, Kyoto University, Sakyo, Kyoto, Japan
| | - Makoto Nishiyama
- Department of Biochemistry, New York University School of Medicine, New York, USA.,Kasah Technology Inc. New York, New York, USA
| | - Kazunobu Togashi
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | | | - Kyonsoo Hong
- Department of Biochemistry, New York University School of Medicine, New York, USA.,Kasah Technology Inc. New York, New York, USA
| | - Shin Ishii
- Imaging Platform for Spatio-temporal Information, Kyoto University, Sakyo, Kyoto, Japan.,Graduate School of Informatics, Kyoto University, Sakyo, Kyoto, Japan
| |
Collapse
|
26
|
Weiss T, Taschner-Mandl S, Bileck A, Slany A, Kromp F, Rifatbegovic F, Frech C, Windhager R, Kitzinger H, Tzou CH, Ambros PF, Gerner C, Ambros IM. Proteomics and transcriptomics of peripheral nerve tissue and cells unravel new aspects of the human Schwann cell repair phenotype. Glia 2016; 64:2133-2153. [DOI: 10.1002/glia.23045] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 07/21/2016] [Accepted: 07/26/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Tamara Weiss
- Children's Cancer Research Institute; Vienna Austria
| | | | - Andrea Bileck
- Department of Analytical Chemistry; University of Vienna; Vienna Austria
| | - Astrid Slany
- Department of Analytical Chemistry; University of Vienna; Vienna Austria
| | - Florian Kromp
- Children's Cancer Research Institute; Vienna Austria
| | | | | | - Reinhard Windhager
- Department of Orthopedic Surgery; Medical University of Vienna; Vienna Austria
| | - Hugo Kitzinger
- Department of Plastic and Reconstructive Surgery; Medical University of Vienna; Vienna Austria
| | - Chieh-Han Tzou
- Department of Plastic and Reconstructive Surgery; Medical University of Vienna; Vienna Austria
| | - Peter F. Ambros
- Children's Cancer Research Institute; Vienna Austria
- Department of Pediatrics; Medical University of Vienna; Vienna Austria
| | - Christopher Gerner
- Department of Analytical Chemistry; University of Vienna; Vienna Austria
| | | |
Collapse
|
27
|
Kono S, Yamamoto H, Kushida T, Hirano-Iwata A, Niwano M, Tanii T. Live-Cell, Label-Free Identification of GABAergic and Non-GABAergic Neurons in Primary Cortical Cultures Using Micropatterned Surface. PLoS One 2016; 11:e0160987. [PMID: 27513933 PMCID: PMC4981301 DOI: 10.1371/journal.pone.0160987] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Accepted: 07/28/2016] [Indexed: 12/21/2022] Open
Abstract
Excitatory and inhibitory neurons have distinct roles in cortical dynamics. Here we present a novel method for identifying inhibitory GABAergic neurons from non-GABAergic neurons, which are mostly excitatory glutamatergic neurons, in primary cortical cultures. This was achieved using an asymmetrically designed micropattern that directs an axonal process to the longest pathway. In the current work, we first modified the micropattern geometry to improve cell viability and then studied the axon length from 2 to 7 days in vitro (DIV). The cell types of neurons were evaluated retrospectively based on immunoreactivity against GAD67, a marker for inhibitory GABAergic neurons. We found that axons of non-GABAergic neurons grow significantly longer than those of GABAergic neurons in the early stages of development. The optimal threshold for identifying GABAergic and non-GABAergic neurons was evaluated to be 110 μm at 6 DIV. The method does not require any fluorescence labelling and can be carried out on live cells. The accuracy of identification was 98.2%. We confirmed that the high accuracy was due to the use of a micropattern, which standardized the development of cultured neurons. The method promises to be beneficial both for engineering neuronal networks in vitro and for basic cellular neuroscience research.
Collapse
Affiliation(s)
- Sho Kono
- Graduate School of Fundamental Science and Engineering, Waseda University, Tokyo, Japan
- Japan Society for the Promotion of Science (JSPS), Tokyo, Japan
| | - Hideaki Yamamoto
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan
| | - Takatoshi Kushida
- Graduate School of Fundamental Science and Engineering, Waseda University, Tokyo, Japan
| | - Ayumi Hirano-Iwata
- Graduate School of Biomedical Engineering, Tohoku University, Sendai, Japan
| | - Michio Niwano
- Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
| | - Takashi Tanii
- Graduate School of Fundamental Science and Engineering, Waseda University, Tokyo, Japan
| |
Collapse
|
28
|
Identification of a shootin1 isoform expressed in peripheral tissues. Cell Tissue Res 2016; 366:75-87. [PMID: 27177867 DOI: 10.1007/s00441-016-2415-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 04/20/2016] [Indexed: 10/24/2022]
Abstract
Shootin1 is a brain-specific cytoplasmic protein involved in neuronal polarity formation and axon outgrowth. It accumulates at the leading edge of axonal growth cones, where it mediates the mechanical coupling between F-actin retrograde flow and cell adhesions as a clutch molecule, thereby producing force for axon outgrowth. In this study, we report a novel splicing isoform of shootin1 which is expressed not only in the brain but also in peripheral tissues. We have renamed the brain-specific shootin1 as shootin1a and termed the novel isoform as shootin1b. Immunoblot and immunohistochemical analyses with a shootin1b-specific antibody revealed that shootin1b is distributed in various mouse tissues including the lung, liver, stomach, intestines, spleen, pancreas, kidney and skin. Interestingly, shootin1b immunoreactivity was widely detected in epithelial cells that constitute simple and stratified epithelia; in some cells, it colocalized with E-cadherin and cortactin at cell-cell contact sites. Shootin1b also localized in dendritic cells in the spleen. These results suggest that shootin1b may function in various peripheral tissues including epithelial cells.
Collapse
|
29
|
Winans AM, Collins SR, Meyer T. Waves of actin and microtubule polymerization drive microtubule-based transport and neurite growth before single axon formation. eLife 2016; 5:e12387. [PMID: 26836307 PMCID: PMC4805541 DOI: 10.7554/elife.12387] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 01/31/2016] [Indexed: 12/16/2022] Open
Abstract
Many developing neurons transition through a multi-polar state with many competing neurites before assuming a unipolar state with one axon and multiple dendrites. Hallmarks of the multi-polar state are large fluctuations in microtubule-based transport into and outgrowth of different neurites, although what drives these fluctuations remains elusive. We show that actin waves, which stochastically migrate from the cell body towards neurite tips, direct microtubule-based transport during the multi-polar state. Our data argue for a mechanical control system whereby actin waves transiently widen the neurite shaft to allow increased microtubule polymerization to direct Kinesin-based transport and create bursts of neurite extension. Actin waves also require microtubule polymerization, arguing that positive feedback links these two components. We propose that actin waves create large stochastic fluctuations in microtubule-based transport and neurite outgrowth, promoting competition between neurites as they explore the environment until sufficient external cues can direct one to become the axon. DOI:http://dx.doi.org/10.7554/eLife.12387.001 Nerve cells (also known as neurons) connect with each other to form complex networks through which signals are carried around the body. Signals are received by branch-like projections called dendrites, pass through the cell body and then pass along a long projection called the axon before being transmitted to the dendrites of neighboring neurons. In animal embryos, immature neurons in part of the brain called the hippocampus – which is crucial for learning and forming memories – develop into mature neurons through a series of steps. In the early stages of development, an immature neuron sends out multiple projections that extend out in all directions from its cell body. These projections randomly retract and lengthen for a while before a single projection grows into an axon and the others become dendrites. It is believed that signal proteins inside the neuron that promote the formation of an axon selectively accumulate in a projection as it grows into an axon. These axon-promoting proteins are carried to the axons by a motor protein called kinesin, which moves along fibers called microtubules. In immature neurons, kinesin motors randomly move in and out of different projections, before settling in the projection that will grow into the axon. However, it is not clear what drives these fluctuations. To address this question, Winans et al. used microscopy to study the transport of axon-promoting proteins in hippocampal neurons. The experiments show that a protein called actin forms a mesh of filaments in a wave-like manner, starting in the cell body and moving outwards into the projections. When a wave of actin reaches a projection, the projection grows for a while and then stops until the next actin wave arrives. Furthermore, the actin waves promote the formation of more microtubule filaments. This work shows that actin waves make the projections wider to create space for more microtubules to form, which increases the transport of axon-promoting proteins to the projections. Winans et al.’s findings suggest that actin waves direct axon-promoting proteins to axons and promote competition between the projections early on by generating random fluctuations that allow all the projections to grow and retract. This would allow each projection to explore its environment in the search for signals that promote axon growth. The next challenge is to understand how different signals select the “winning axon”. DOI:http://dx.doi.org/10.7554/eLife.12387.002
Collapse
Affiliation(s)
- Amy M Winans
- Biophysics Program, Stanford University, Stanford, United States.,Department of Chemical and Systems Biology, Stanford University, Stanford, United States.,Center for Systems Biology, Stanford University, Stanford, United States
| | - Sean R Collins
- Department of Chemical and Systems Biology, Stanford University, Stanford, United States.,Center for Systems Biology, Stanford University, Stanford, United States
| | - Tobias Meyer
- Department of Chemical and Systems Biology, Stanford University, Stanford, United States.,Center for Systems Biology, Stanford University, Stanford, United States
| |
Collapse
|
30
|
Mironov VI, Semyanov AV, Kazantsev VB. Dendrite and Axon Specific Geometrical Transformation in Neurite Development. Front Comput Neurosci 2016; 9:156. [PMID: 26858635 PMCID: PMC4729915 DOI: 10.3389/fncom.2015.00156] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 12/24/2015] [Indexed: 01/02/2023] Open
Abstract
We propose a model of neurite growth to explain the differences in dendrite and axon specific neurite development. The model implements basic molecular kinetics, e.g., building protein synthesis and transport to the growth cone, and includes explicit dependence of the building kinetics on the geometry of the neurite. The basic assumption was that the radius of the neurite decreases with length. We found that the neurite dynamics crucially depended on the relationship between the rate of active transport and the rate of morphological changes. If these rates were in the balance, then the neurite displayed axon specific development with a constant elongation speed. For dendrite specific growth, the maximal length was rapidly saturated by degradation of building protein structures or limited by proximal part expansion reaching the characteristic cell size.
Collapse
Affiliation(s)
- Vasily I Mironov
- Department of Neurotechnologies, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod, Russia
| | - Alexey V Semyanov
- Department of Neurotechnologies, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny Novgorod Nizhny Novgorod, Russia
| | - Victor B Kazantsev
- Department of Neurotechnologies, Institute of Biology and Biomedicine, Lobachevsky State University of Nizhny NovgorodNizhny Novgorod, Russia; Laboratory of Nonlinear Dynamics of Living Systems, Institute of Applied Physics of the Russian Academy of ScienceNizhny Novgorod, Russia
| |
Collapse
|
31
|
Regulation of Shootin1 Gene Expression Involves NGF-induced Alternative Splicing during Neuronal Differentiation of PC12 Cells. Sci Rep 2015; 5:17931. [PMID: 26648138 PMCID: PMC4673418 DOI: 10.1038/srep17931] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 11/06/2015] [Indexed: 11/08/2022] Open
Abstract
Shootin1 is a protein involved in neuronal polarization, and has been shown to be a key molecule for the positive/negative feedback loop for axon induction required during neuronal symmetry breaking. To better understand the molecular basis of shootin1 dynamics, we analysed the regulatory pathways and the expressional status of shootin1 gene during NGF-induced neuronal differentiation. We demonstrated that the isoform-1 and isoform-2 of shootin1 is differentially expressed during neuronal differentiation. By blocking individual downstream pathways of NGF signalling, we found that PI3K/Akt pathway plays a major role in the expression of shootin1 isoform-2. Western blot and RT-PCR results showed that the isoform-1 of shootin1 is constitutively expressed, while the isoform-2 is expressed in a manner that is strictly dependent on NGF-stimulation. Isoform-specific RT-PCR results demonstrated that the differential expression of the isoform-1 and isoform-2 of shootin1 is a consequence of alternative splicing of shootin1 pre-mRNA, in response to NGF-signalling. Collectively these findings provide the first information on the molecular mechanisms regulating the expression of shootin1 gene and represent the first example of NGF-induced alternative splicing process that has a regulatory role in neuritogenesis.
Collapse
|
32
|
Namba T, Funahashi Y, Nakamuta S, Xu C, Takano T, Kaibuchi K. Extracellular and Intracellular Signaling for Neuronal Polarity. Physiol Rev 2015; 95:995-1024. [PMID: 26133936 DOI: 10.1152/physrev.00025.2014] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Neurons are one of the highly polarized cells in the body. One of the fundamental issues in neuroscience is how neurons establish their polarity; therefore, this issue fascinates many scientists. Cultured neurons are useful tools for analyzing the mechanisms of neuronal polarization, and indeed, most of the molecules important in their polarization were identified using culture systems. However, we now know that the process of neuronal polarization in vivo differs in some respects from that in cultured neurons. One of the major differences is their surrounding microenvironment; neurons in vivo can be influenced by extrinsic factors from the microenvironment. Therefore, a major question remains: How are neurons polarized in vivo? Here, we begin by reviewing the process of neuronal polarization in culture conditions and in vivo. We also survey the molecular mechanisms underlying neuronal polarization. Finally, we introduce the theoretical basis of neuronal polarization and the possible involvement of neuronal polarity in disease and traumatic brain injury.
Collapse
Affiliation(s)
- Takashi Namba
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yasuhiro Funahashi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shinichi Nakamuta
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Chundi Xu
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tetsuya Takano
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Kozo Kaibuchi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| |
Collapse
|
33
|
Kubo Y, Baba K, Toriyama M, Minegishi T, Sugiura T, Kozawa S, Ikeda K, Inagaki N. Shootin1-cortactin interaction mediates signal-force transduction for axon outgrowth. J Cell Biol 2015; 210:663-76. [PMID: 26261183 PMCID: PMC4539990 DOI: 10.1083/jcb.201505011] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 06/26/2015] [Indexed: 11/22/2022] Open
Abstract
The shootin1–cortactin interaction participates in netrin-1–induced F-actin–adhesion coupling and in the promotion of traction forces for axon outgrowth. Motile cells transduce environmental chemical signals into mechanical forces to achieve properly controlled migration. This signal–force transduction is thought to require regulated mechanical coupling between actin filaments (F-actins), which undergo retrograde flow at the cellular leading edge, and cell adhesions via linker “clutch” molecules. However, the molecular machinery mediating this regulatory coupling remains unclear. Here we show that the F-actin binding molecule cortactin directly interacts with a clutch molecule, shootin1, in axonal growth cones, thereby mediating the linkage between F-actin retrograde flow and cell adhesions through L1-CAM. Shootin1–cortactin interaction was enhanced by shootin1 phosphorylation by Pak1, which is activated by the axonal chemoattractant netrin-1. We provide evidence that shootin1–cortactin interaction participates in netrin-1–induced F-actin adhesion coupling and in the promotion of traction forces for axon outgrowth. Under cell signaling, this regulatory F-actin adhesion coupling in growth cones cooperates with actin polymerization for efficient cellular motility.
Collapse
Affiliation(s)
- Yusuke Kubo
- Laboratory of Systems Neurobiology and Medicine, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Kentarou Baba
- Laboratory of Systems Neurobiology and Medicine, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Michinori Toriyama
- Laboratory of Systems Neurobiology and Medicine, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Takunori Minegishi
- Laboratory of Systems Neurobiology and Medicine, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Tadao Sugiura
- Laboratory of Biomedical Imaging, Graduate School of Information Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Satoshi Kozawa
- Mathematical Informatics, Graduate School of Information Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Kazushi Ikeda
- Mathematical Informatics, Graduate School of Information Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| |
Collapse
|
34
|
Actin Migration Driven by Directional Assembly and Disassembly of Membrane-Anchored Actin Filaments. Cell Rep 2015; 12:648-60. [DOI: 10.1016/j.celrep.2015.06.048] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 05/18/2015] [Accepted: 06/11/2015] [Indexed: 11/24/2022] Open
|
35
|
Guo CL, Cheng PL. Second messenger signaling for neuronal polarization: cell mechanics-dependent pattern formation. Dev Neurobiol 2014; 75:388-401. [PMID: 25059891 DOI: 10.1002/dneu.22217] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 07/23/2014] [Accepted: 07/23/2014] [Indexed: 01/13/2023]
Abstract
Neuronal polarization is a critical step in the neuronal morphogenesis. Despite the identification of several evolutionarily conserved factors for neural polarization, the exact mechanisms by which cells initiate and maintain polarity remain to be characterized. Here, we review the recent progress on the roles of second messengers, specifically the cyclic nucleotides and membrane-associated phospholipids, in the initiation, propagation, and integration of polarization signals, and propose an inhibitor-free model for neural polarization. The characteristic features of neuron polarization include the formation of single axon and multiple dendrites. These features involve chemical and mechanical mechanisms such as reaction-diffusion and tug-of-war, by which second messengers can act in concert to initiate and stabilize the cellular asymmetry. Nevertheless, biochemical factors eliciting the long-range inhibition remain ambiguous. Thus, we provide a simple, inhibitor-free model that can incorporate known cytochemical and cytomechanical factors, and produce features of neuronal polarization in environments provided with minimized extracellular regulators.
Collapse
Affiliation(s)
- Chin-Lin Guo
- Institute of Physics, Academia Sinica, Taipei, 11529, Taiwan
| | | |
Collapse
|
36
|
Mironov VI, Romanov AS, Simonov AY, Vedunova MV, Kazantsev VB. Oscillations in a neurite growth model with extracellular feedback. Neurosci Lett 2014; 570:16-20. [PMID: 24686176 DOI: 10.1016/j.neulet.2014.03.041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 03/03/2014] [Accepted: 03/14/2014] [Indexed: 10/25/2022]
Abstract
We consider the influence of extracellular signalling on neurite elongation in a model of neurite growth mediated by building proteins (e.g., tubulin). The tubulin production dynamics were supplied by a function describing the influence of extracellular signalling, which can promote or depress neurite elongation. We found that this extracellular feedback could generate neurite length oscillations consisting of a periodic sequence of elongations and retractions. The oscillations prevent further outgrowth of the neurite, which becomes trapped in the non-uniform extracellular field. We analysed the characteristics of the elongation process for different distributions of attracting and repelling sources of the extracellular signalling molecules. The model predicts three different scenarios of neurite development in the extracellular field, including monotonic and oscillatory outgrowth, localised limit cycle oscillations and complete growth depression.
Collapse
Affiliation(s)
- V I Mironov
- Nizhny Novgorod Neuroscience Centre, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia.
| | - A S Romanov
- Nizhny Novgorod Neuroscience Centre, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - A Yu Simonov
- Nizhny Novgorod Neuroscience Centre, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - M V Vedunova
- Nizhny Novgorod Neuroscience Centre, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - V B Kazantsev
- Nizhny Novgorod Neuroscience Centre, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia; Laboratory of Nonlinear Dynamics of Living Systems, Institute of Applied Physics of Russian Academy of Science, Nizhny Novgorod, Russia
| |
Collapse
|
37
|
Zuccaro E, Bergami M, Vignoli B, Bony G, Pierchala BA, Santi S, Cancedda L, Canossa M. Polarized expression of p75(NTR) specifies axons during development and adult neurogenesis. Cell Rep 2014; 7:138-52. [PMID: 24685135 DOI: 10.1016/j.celrep.2014.02.039] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2012] [Revised: 02/10/2014] [Accepted: 02/20/2014] [Indexed: 01/07/2023] Open
Abstract
VIDEO ABSTRACT Newly generated neurons initiate polarizing signals that specify a single axon and multiple dendrites, a process critical for patterning neuronal circuits in vivo. Here, we report that the pan-neurotrophin receptor p75(NTR) is a polarity regulator that localizes asymmetrically in differentiating neurons in response to neurotrophins and is required for specification of the future axon. In cultured hippocampal neurons, local exposure to neurotrophins causes early accumulation of p75(NTR) into one undifferentiated neurite to specify axon fate. Moreover, knockout or knockdown of p75(NTR) results in failure to initiate an axon in newborn neurons upon cell-cycle exit in vitro and in the developing cortex, as well as during adult hippocampal neurogenesis in vivo. Hence, p75(NTR) governs neuronal polarity, determining pattern and assembly of neuronal circuits in adult hippocampus and cortical development.
Collapse
Affiliation(s)
- Emanuela Zuccaro
- Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), via Morego 30, I-16163 Genoa, Italy
| | - Matteo Bergami
- Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), via Morego 30, I-16163 Genoa, Italy; Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), University Hospital of Cologne, Joseph-Stelzmann-Strasse 26, Cologne, Germany
| | - Beatrice Vignoli
- Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), via Morego 30, I-16163 Genoa, Italy
| | - Guillaume Bony
- Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), via Morego 30, I-16163 Genoa, Italy
| | - Brian A Pierchala
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, 1011 N. University Avenue, Ann Arbor, MI 48109, USA
| | - Spartaco Santi
- National Research Council (CNR), Institute of Molecular Genetics (IGM)-Bologna, Laboratory of Muscoloskeletal Cell Biology, IOR, via di Barbiano1/10, I-40136 Bologna, Italy
| | - Laura Cancedda
- Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), via Morego 30, I-16163 Genoa, Italy.
| | - Marco Canossa
- Department of Neuroscience and Brain Technologies, Italian Institute of Technology (IIT), via Morego 30, I-16163 Genoa, Italy; European Brain Research Institute (EBRI) "Rita Levi-Montalcini," via del Fosso di Fiorano 64/65, I-00143 Rome, Italy.
| |
Collapse
|
38
|
Hjorth JJJ, van Pelt J, Mansvelder HD, van Ooyen A. Competitive dynamics during resource-driven neurite outgrowth. PLoS One 2014; 9:e86741. [PMID: 24498280 PMCID: PMC3911915 DOI: 10.1371/journal.pone.0086741] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 12/17/2013] [Indexed: 11/18/2022] Open
Abstract
Neurons form networks by growing out neurites that synaptically connect to other neurons. During this process, neurites develop complex branched trees. Interestingly, the outgrowth of neurite branches is often accompanied by the simultaneous withdrawal of other branches belonging to the same tree. This apparent competitive outgrowth between branches of the same neuron is relevant for the formation of synaptic connectivity, but the underlying mechanisms are unknown. An essential component of neurites is the cytoskeleton of microtubules, long polymers of tubulin dimers running throughout the entire neurite. To investigate whether competition between neurites can emerge from the dynamics of a resource such as tubulin, we developed a multi-compartmental model of neurite growth. In the model, tubulin is produced in the soma and transported by diffusion and active transport to the growth cones at the tip of the neurites, where it is assembled into microtubules to elongate the neurite. Just as in experimental studies, we find that the outgrowth of a neurite branch can lead to the simultaneous retraction of its neighboring branches. We show that these competitive interactions occur in simple neurite morphologies as well as in complex neurite arborizations and that in developing neurons competition for a growth resource such as tubulin can account for the differential outgrowth of neurite branches. The model predicts that competition between neurite branches decreases with path distance between growth cones, increases with path distance from growth cone to soma, and decreases with a higher rate of active transport. Together, our results suggest that competition between outgrowing neurites can already emerge from relatively simple and basic dynamics of a growth resource. Our findings point to the need to test the model predictions and to determine, by monitoring tubulin concentrations in outgrowing neurons, whether tubulin is the resource for which neurites compete.
Collapse
Affiliation(s)
- J J Johannes Hjorth
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Jaap van Pelt
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| | - Arjen van Ooyen
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
39
|
Naoki H, Ishii S. Mathematical modeling of neuronal polarization during development. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2014; 123:127-41. [PMID: 24560143 DOI: 10.1016/b978-0-12-397897-4.00003-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/24/2023]
Abstract
During development of the brain, morphogenesis of neurons is dynamically organized from a simple rounded shape to a highly polarized morphology consisting of soma, one axon, and dendrites, which is a basis for establishing the unidirectional transfer of electric signals between neurons. The mechanism of such polarization is thought to be "local activation-global inhibition"; however, globally diffusing inhibitor molecules have not been identified. In this chapter, we present a theoretical modeling approach of such neuronal development. We first summarize biological research on neuronal polarization and then develop a biophysical model. Through mathematical analysis, principles of local activation-global inhibition are illustrated based on active transport, protein degradation, and neurite growth, but not on globally diffusing inhibitor.
Collapse
Affiliation(s)
- Honda Naoki
- Imaging Platform for Spatio-Temporal Information, Graduate School of Medicine, Kyoto University, Kyoto, Kyoto, Japan
| | - Shin Ishii
- Graduate School of Informatics, Kyoto University, Uji, Kyoto, Japan
| |
Collapse
|
40
|
Abstract
Shootin1 has been ascribed a role in regulating polarization of primary hippocampal neurons. To better understand the possible role of Shootin1 in the developing brain, we identified a member of the kinesin superfamily, KIF20B, as a novel Shootin1 interacting protein and a potential mediator of Shootin1 interaction with microtubules. KIF20B/Shootin1 binding was mapped to a 57 aa KIF20B sequence, which was used as a dominant-negative fragment. Direct interaction between that peptide (MBD) and Shootin1 was confirmed by surface plasmon resonance-based technology and the affinity was determined in the 10⁻⁷ m range. The proteins are expressed in the developing brain and formed a complex in vivo based on coimmunoprecipitation experiments and coimmunostaining in primary neurons. In primary hippocampal neurons Kif20b knockdown reduced Shootin1 mobilization to the developing axon, as evidenced by immunostaining and fluorescence recovery after photobleaching analysis, suggesting that Shootin1 is a novel KIF20B cargo. shRNA targeting of Shootin1 reduced PIP3 accumulation in the growth cone, as did Kif20b shRNA. In the developing mouse brain, Kif20b knockdown or expression of the KIF20B minimal binding domain inhibited neuronal migration, and in vivo migration assays suggested that Shootin1/Kif20b acts in the same genetic pathway. Time-lapse imaging of multipolar cells in the subventricular zone revealed that downregulating levels of either Shootin1 or Kif20b hindered the transition from multipolar to bipolar cells. Collectively, our data demonstrate the importance of the Shootin1/KIF20B interaction to the dynamic process of pyramidal neuronal polarization and migration.
Collapse
|
41
|
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
|
42
|
Albus CA, Rishal I, Fainzilber M. Cell length sensing for neuronal growth control. Trends Cell Biol 2013; 23:305-10. [PMID: 23511112 DOI: 10.1016/j.tcb.2013.02.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 02/03/2013] [Accepted: 02/11/2013] [Indexed: 11/27/2022]
Abstract
Neurons exhibit great size differences, and must coordinate biosynthesis rates in cell bodies with the growth needs of different lengths of axons. Classically, axon growth has been viewed mainly as a consequence of extrinsic influences. However, recent publications have proposed at least two different intrinsic axon growth-control mechanisms. We suggest that these mechanisms form part of a continuum of axon growth-control mechanisms, wherein initial growth rates are pre-programmed by transcription factor levels, and subsequent elongating growth is dependent on feedback from intrinsic length-sensing enabled by bidirectional motor-dependent oscillating signals. This model might explain intrinsic limits on elongating neuronal growth and provides a mechanistic framework for determining the connections between genome expression and cellular growth rates in neurons.
Collapse
Affiliation(s)
- Christin A Albus
- Department of Biological Chemistry, Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | |
Collapse
|
43
|
Rishal I, Kam N, Perry RBT, Shinder V, Fisher EMC, Schiavo G, Fainzilber M. A motor-driven mechanism for cell-length sensing. Cell Rep 2013; 1:608-16. [PMID: 22773964 PMCID: PMC3389498 DOI: 10.1016/j.celrep.2012.05.013] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Size homeostasis is fundamental in cell biology, but it is not clear how large cells such as neurons can assess their own size or length. We examined a role for molecular motors in intracellular length sensing. Computational simulations suggest that spatial information can be encoded by the frequency of an oscillating retrograde signal arising from a composite negative feedback loop between bidirectional motor-dependent signals. The model predicts that decreasing either or both anterograde or retrograde signals should increase cell length, and this prediction was confirmed upon application of siRNAs for specific kinesin and/or dynein heavy chains in adult sensory neurons. Heterozygous dynein heavy chain 1 mutant sensory neurons also exhibited increased lengths both in vitro and during embryonic development. Moreover, similar length increases were observed in mouse embryonic fibroblasts upon partial downregulation of dynein heavy chain 1. Thus, molecular motors critically influence cell-length sensing and growth control.
Collapse
Affiliation(s)
- Ida Rishal
- Department of Biological Chemistry, Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | | | | | | | | | |
Collapse
|
44
|
Synchronous symmetry breaking in neurons with different neurite counts. PLoS One 2013; 8:e54905. [PMID: 23408951 PMCID: PMC3569465 DOI: 10.1371/journal.pone.0054905] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2012] [Accepted: 12/17/2012] [Indexed: 11/19/2022] Open
Abstract
As neurons develop, several immature processes (i.e., neurites) grow out of the cell body. Over time, each neuron breaks symmetry when only one of its neurites grows much longer than the rest, becoming an axon. This symmetry breaking is an important step in neurodevelopment, and aberrant symmetry breaking is associated with several neuropsychiatric diseases, including schizophrenia and autism. However, the effects of neurite count in neuronal symmetry breaking have never been studied. Existing models for neuronal polarization disagree: some predict that neurons with more neurites polarize up to several days later than neurons with fewer neurites, while others predict that neurons with different neurite counts polarize synchronously. We experimentally find that neurons with different neurite counts polarize synchronously. We also show that despite the significant differences among the previously proposed models, they all agree with our experimental findings when the expression levels of the proteins responsible for symmetry breaking increase with neurite count. Consistent with these results, we observe that the expression levels of two of these proteins, HRas and shootin1, significantly correlate with neurite count. This coordinated symmetry breaking we observed among neurons with different neurite counts may be important for synchronized polarization of neurons in developing organisms.
Collapse
|
45
|
Yamamoto H, Demura T, Morita M, Banker GA, Tanii T, Nakamura S. Differential neurite outgrowth is required for axon specification by cultured hippocampal neurons. J Neurochem 2012; 123:904-10. [PMID: 22928776 DOI: 10.1111/jnc.12001] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2012] [Revised: 08/22/2012] [Accepted: 08/24/2012] [Indexed: 11/28/2022]
Abstract
Formation of an axon is the first morphological evidence of neuronal polarization, visible as a profound outgrowth of the axon compared with sibling neurites. One unsolved question on the mechanism of axon formation is the role of axon outgrowth in axon specification. This question was difficult to assess, because neurons freely extend their neurites in a conventional culture. Here, we leveraged surface nano/micro-modification techniques to fabricate a template substrate for constraining neurite lengths of cultured neurons. Using the template, we asked (i) Do neurons polarize even if all neurites cannot grow sufficiently long? (ii) Would the neurite be fated to become an axon if only one was allowed to grow long? A pattern with symmetrical short paths (20 μm) was used to address the former question, and an asymmetrical pattern with one path extended to 100 μm for the latter. Axon formation was evaluated by tau-1/MAP2 immunostaining and live-cell imaging of constitutively-active kinesin-1. We found that (1) neurons cannot polarize when extension of all neurites is restricted and that (2) when only a single neurite is permitted to grow long, neurons polarize and the longest neurite becomes the axon. These results provide clear evidence that axon outgrowth is required for its specification.
Collapse
Affiliation(s)
- Hideaki Yamamoto
- Department of Life Science and Biotechnology, Tokyo University of Agriculture and Technology, Tokyo, Japan.
| | | | | | | | | | | |
Collapse
|
46
|
Williams RR, Pearse DD, Tresco PA, Bunge MB. The assessment of adeno-associated vectors as potential intrinsic treatments for brainstem axon regeneration. J Gene Med 2012; 14:20-34. [PMID: 22106053 DOI: 10.1002/jgm.1628] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Adeno-associated virus (AAV) vector-mediated transgene expression is a promising therapeutic to change the intrinsic state of neurons and promote repair after central nervous system injury. Given that numerous transgenes have been identified as potential candidates, the present study demonstrates how to determine whether their expression by AAV has a direct intrinsic effect on axon regeneration. METHODS Serotype 2 AAV-enhanced green fluorescent protein (EGFP) was stereotaxically injected into the brainstem of adult rats, followed by a complete transection of the thoracic spinal cord and Schwann cell (SC) bridge implantation. RESULTS The expression of EGFP in brainstem neurons labeled numerous axons in the thoracic spinal cord and that regenerated into the SC bridge. The number of EGFP-labeled axons rostral to the bridge directly correlated with the number of EGFP-labeled axons that regenerated into the bridge. Animals with a greater number of EGFP-labeled axons rostral to the bridge exhibited an increased percentage of those axons found near the distal end of the bridge compared to animals with a lesser number. This suggested that EGFP may accumulate distally in the axon with time, enabling easier visualization. By labeling brainstem axons with EGFP before injury, numerous axon remnants undergoing Wallerian degeneration may be identified distal to the complete transection up to 6 weeks after injury. CONCLUSIONS Serotype 2 AAV-EGFP enabled easy visualization of brainstem axon regeneration. Rigorous models of axonal injury (i.e. complete transection and cell implantation) should be used in combination with AAV-EGFP to directly assess AAV-mediated expression of therapeutic transgenes as intrinsic treatments to improve axonal regeneration.
Collapse
Affiliation(s)
- Ryan R Williams
- University of Miami Miller School of Medicine, The Miami Project to Cure Paralysis, Miami, FL 33136, USA.
| | | | | | | |
Collapse
|
47
|
Affiliation(s)
- Pei-lin Cheng
- Institute of Molecular Biology, Academia Sinica, Taipei 11529, Taiwan;
| | - Mu-ming Poo
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, California, 94720, USA;
| |
Collapse
|
48
|
Hatanaka Y, Yamauchi K. Excitatory cortical neurons with multipolar shape establish neuronal polarity by forming a tangentially oriented axon in the intermediate zone. ACTA ACUST UNITED AC 2012; 23:105-13. [PMID: 22267309 DOI: 10.1093/cercor/bhr383] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The formation of axon-dendrite polarity is crucial for neuron to make the proper information flow within the brain. Although the processes of neuronal polarity formation have been extensively studied using neurons in dissociated culture, the corresponding developmental processes in vivo are still unclear. Here, we illuminate the initial steps of morphological polarization of excitatory cortical neurons in situ, by sparsely labeling their neuroepithelial progenitors using in utero electroporation and then examining their neuronal progeny in brain sections and in slice cultures. Morphological analysis showed that an axon-like long tangential process formed in progeny cells in the intermediate zone (IZ). Time-lapse imaging analysis using slice culture revealed that progeny cells with multipolar shape, after alternately extending and retracting their short processes for several hours, suddenly elongated a long process tangentially. These cells then transformed into a bipolar shape, extending a pia-directed leading process, and migrated radially leaving the tangential process behind, which gave rise to an "L-shaped" axon. Our findings suggest that neuronal polarity in these cells is established de novo from a nonpolarized stage in vivo and indicate that excitatory cortical neurons with multipolar shape in the IZ initiate axon outgrowth before radial migration into the cortical plate.
Collapse
Affiliation(s)
- Yumiko Hatanaka
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan.
| | | |
Collapse
|
49
|
Greene AC, Washburn CM, Bachand GD, James CD. Combined chemical and topographical guidance cues for directing cytoarchitectural polarization in primary neurons. Biomaterials 2011; 32:8860-9. [DOI: 10.1016/j.biomaterials.2011.08.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Accepted: 08/04/2011] [Indexed: 11/28/2022]
|
50
|
Abstract
The formation of axon/dendrite polarity is critical for the neuron to perform its signaling function in the brain. Recent advance in our understanding of cellular and molecular mechanisms underlying the development and maintenance of neuronal polarity has been greatly facilitated by the use of the culture system of dissociated hippocampal neurons. Among many polarization-related proteins, we here focus on the mammalian LKB1, the counterpart of the C. elegans Par-4, which is an upstream regulator among six Par (partitioning-defective) genes that act as master regulators of cell polarity in different cell types across evolutionary distant species. Recent studies have identified LKB1 and its downstream targets SAD/MARK kinases (mammalian homologs of Par-1) as key regulators of neuronal polarization and axon development in cultured neurons and in developing cortical neurons in vivo. We will review the properties of and interactions among proteins in this LKB1-SAD/MARK pathway, drawing upon information obtained from both neuronal and non-neuronal systems. Due to central role of the protein kinase A-dependent phosphorylation of LKB1 in the activation of this pathway, we will review recent findings on how cAMP and cGMP signaling may serve as antagonistic second messengers for axon/dendrite development, and how these cyclic nucleotides may mediate the action of extracellular polarizing factors by modulating the activity of the LKB1-SAD/MARK pathway.
Collapse
Affiliation(s)
- Maya Shelly
- Department of Neurobiology and Behavior, State University of New York, Stony Brook, NY 11794-5230, USA.
| | | |
Collapse
|