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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.
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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.
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2
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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.
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3
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Motz CT, Kabat V, Saxena T, Bellamkonda RV, Zhu C. Neuromechanobiology: An Expanding Field Driven by the Force of Greater Focus. Adv Healthc Mater 2021; 10:e2100102. [PMID: 34342167 PMCID: PMC8497434 DOI: 10.1002/adhm.202100102] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 07/06/2021] [Indexed: 12/14/2022]
Abstract
The brain processes information by transmitting signals through highly connected and dynamic networks of neurons. Neurons use specific cellular structures, including axons, dendrites and synapses, and specific molecules, including cell adhesion molecules, ion channels and chemical receptors to form, maintain and communicate among cells in the networks. These cellular and molecular processes take place in environments rich of mechanical cues, thus offering ample opportunities for mechanical regulation of neural development and function. Recent studies have suggested the importance of mechanical cues and their potential regulatory roles in the development and maintenance of these neuronal structures. Also suggested are the importance of mechanical cues and their potential regulatory roles in the interaction and function of molecules mediating the interneuronal communications. In this review, the current understanding is integrated and promising future directions of neuromechanobiology are suggested at the cellular and molecular levels. Several neuronal processes where mechanics likely plays a role are examined and how forces affect ligand binding, conformational change, and signal induction of molecules key to these neuronal processes are indicated, especially at the synapse. The disease relevance of neuromechanobiology as well as therapies and engineering solutions to neurological disorders stemmed from this emergent field of study are also discussed.
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Affiliation(s)
- Cara T Motz
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Victoria Kabat
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
| | - Tarun Saxena
- Department of Biomedical Engineering, Duke University, Durham, NC, 27709, USA
| | - Ravi V Bellamkonda
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC, 27708, USA
| | - Cheng Zhu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- Parker H. Petit Institute for Bioengineering and Biosciences, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
- George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0363, USA
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4
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Raj V, Jagadish C, Gautam V. Understanding, engineering, and modulating the growth of neural networks: An interdisciplinary approach. BIOPHYSICS REVIEWS 2021; 2:021303. [PMID: 38505122 PMCID: PMC10903502 DOI: 10.1063/5.0043014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 05/25/2021] [Indexed: 03/21/2024]
Abstract
A deeper understanding of the brain and its function remains one of the most significant scientific challenges. It not only is required to find cures for a plethora of brain-related diseases and injuries but also opens up possibilities for achieving technological wonders, such as brain-machine interface and highly energy-efficient computing devices. Central to the brain's function is its basic functioning unit (i.e., the neuron). There has been a tremendous effort to understand the underlying mechanisms of neuronal growth on both biochemical and biophysical levels. In the past decade, this increased understanding has led to the possibility of controlling and modulating neuronal growth in vitro through external chemical and physical methods. We provide a detailed overview of the most fundamental aspects of neuronal growth and discuss how researchers are using interdisciplinary ideas to engineer neuronal networks in vitro. We first discuss the biochemical and biophysical mechanisms of neuronal growth as we stress the fact that the biochemical or biophysical processes during neuronal growth are not independent of each other but, rather, are complementary. Next, we discuss how utilizing these fundamental mechanisms can enable control over neuronal growth for advanced neuroengineering and biomedical applications. At the end of this review, we discuss some of the open questions and our perspectives on the challenges and possibilities related to controlling and engineering the growth of neuronal networks, specifically in relation to the materials, substrates, model systems, modulation techniques, data science, and artificial intelligence.
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Affiliation(s)
- Vidur Raj
- Department of Electronic Materials Engineering, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | | | - Vini Gautam
- Department of Biomedical Engineering, Faculty of Engineering and Information Technology, The University of Melbourne, Melbourne, Victoria 3010, Australia
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5
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Involvement of JNK1 in Neuronal Polarization During Brain Development. Cells 2020; 9:cells9081897. [PMID: 32823764 PMCID: PMC7466125 DOI: 10.3390/cells9081897] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 08/06/2020] [Accepted: 08/10/2020] [Indexed: 12/16/2022] Open
Abstract
The c-Jun N-terminal Kinases (JNKs) are a group of regulatory elements responsible for the control of a wide array of functions within the cell. In the central nervous system (CNS), JNKs are involved in neuronal polarization, starting from the cell division of neural stem cells and ending with their final positioning when migrating and maturing. This review will focus mostly on isoform JNK1, the foremost contributor of total JNK activity in the CNS. Throughout the text, research from multiple groups will be summarized and discussed in order to describe the involvement of the JNKs in the different steps of neuronal polarization. The data presented support the idea that isoform JNK1 is highly relevant to the regulation of many of the processes that occur in neuronal development in the CNS.
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6
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Gong A, Rode S, Kaupp UB, Gompper G, Elgeti J, Friedrich BM, Alvarez L. The steering gaits of sperm. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190149. [PMID: 31884910 PMCID: PMC7017342 DOI: 10.1098/rstb.2019.0149] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/24/2019] [Indexed: 11/25/2022] Open
Abstract
Sperm are highly specialized cells, which have been subject to substantial evolutionary pressure. Whereas some sperm features are highly conserved, others have undergone major modifications. Some of these variations are driven by adaptation to mating behaviours or fitness at the organismic level. Others represent alternative solutions to the same task. Sperm must find the egg for fertilization. During this task, sperm rely on long slender appendages termed flagella that serve as sensory antennas, propellers and steering rudders. The beat of the flagellum is periodic. The resulting travelling wave generates the necessary thrust for propulsion in the fluid. Recent studies reveal that, for steering, different species rely on different fundamental features of the beat wave. Here, we discuss some examples of unity and diversity across sperm from different species with a particular emphasis on the steering mechanisms. This article is part of the Theo Murphy meeting issue 'Unity and diversity of cilia in locomotion and transport'.
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Affiliation(s)
- A. Gong
- Center of Advanced European Studies and Research (CAESAR), Molecular Sensory Systems, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - S. Rode
- Theoretical Soft Matter and Biophysics, Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - U. B. Kaupp
- Center of Advanced European Studies and Research (CAESAR), Molecular Sensory Systems, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
| | - G. Gompper
- Theoretical Soft Matter and Biophysics, Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - J. Elgeti
- Theoretical Soft Matter and Biophysics, Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - B. M. Friedrich
- Biological Algorithms Group, TU Dresden, Biological Systems Path of the Center for Advancing Electronics Dresden (CFAED), Helmholtzstrasse 18, 01069 Dresden, Germany
| | - L. Alvarez
- Center of Advanced European Studies and Research (CAESAR), Molecular Sensory Systems, Ludwig-Erhard-Allee 2, 53175 Bonn, Germany
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7
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Bing T, Zhang N, Shangguan D. Cell-SELEX, an Effective Way to the Discovery of Biomarkers and Unexpected Molecular Events. ACTA ACUST UNITED AC 2019; 3:e1900193. [PMID: 32648677 DOI: 10.1002/adbi.201900193] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 09/26/2019] [Indexed: 12/15/2022]
Abstract
Cell-SELEX can not only generate aptamers for specific cell isolation/detection, diagnosis, and therapy, but also lead to the discovery of biomarkers and unexpected molecular events. However, most cell-SELEX research is concentrated on aptamer generation and applications. In this progress report, recent research progress with cell-SELEX in terms of the discovery of biomarkers and unexpected molecular events is highlighted. In particular, the key technical challenges for cell-SELEX-based biomarker discovery, namely, the methods for identification and validation of target proteins of aptamers, are discussed in detail. Finally, the prospects of the applications of cell-SELEX in this field now and in the near future are described. It is expected that this report will attract attention to the benefit of cell-SELEX and provide a practical reference for biomedical researchers.
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Affiliation(s)
- Tao Bing
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Nan Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dihua Shangguan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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8
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Urasaki A, Morishita S, Naka K, Uozumi M, Abe K, Huang L, Watase E, Nakagawa O, Kawakami K, Matsui T, Bessho Y, Inagaki N. Shootins mediate collective cell migration and organogenesis of the zebrafish posterior lateral line system. Sci Rep 2019; 9:12156. [PMID: 31434971 PMCID: PMC6704158 DOI: 10.1038/s41598-019-48585-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/07/2019] [Indexed: 01/23/2023] Open
Abstract
The zebrafish sensory posterior lateral line is an excellent model system to study collective cell migration and organogenesis. Shootin1 is a cytoplasmic protein involved in neuronal polarization and axon guidance. Previous studies have shown that shootin1 couples actin filament retrograde flow with extracellular adhesive substrates at the leading edge of axonal growth cones, thereby producing mechanical force for the migration and guidance of axonal growth cones. However, the functions of shootin in peripheral cells remain unknown. Here we identified two novel shootin family members, shootin2 and shootin3. In zebrafish, shootin1 and shootin3 are expressed in the posterior lateral line primordium (PLLP) and neuromasts during embryonic development. A shootin1 mutant displayed a reduced speed of PLLP migration, while shootin1;shootin3 double mutation inhibited cell proliferation in the PLLP. Furthermore, our results suggest that shootin1 and shootin3 positively regulate the number of neuromasts and the number of cells in deposited neuromasts. Our study demonstrates that shootins mediate collective cell migration of the posterior lateral line primordium and formation of neuromasts in zebrafish.
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Affiliation(s)
- Akihiro Urasaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.,Department of Molecular Physiology, National Cerebral and Cardiovascular Center Research Institute, 6-1 Kishibe-Shinmachi, Suita, Osaka, 564-8565, Japan
| | - Seiya Morishita
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Kosuke Naka
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Minato Uozumi
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Kouki Abe
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Liguo Huang
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Emiko Watase
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Osamu Nakagawa
- Department of Molecular Physiology, National Cerebral and Cardiovascular Center Research Institute, 6-1 Kishibe-Shinmachi, Suita, Osaka, 564-8565, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, and Department of Genetics, SOKENDAI (The Graduate University for Advanced Studies), Mishima, Shizuoka, 411-8540, Japan
| | - Takaaki Matsui
- Laboratory of Gene Regulation Research, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Yasumasa Bessho
- Laboratory of Gene Regulation Research, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan
| | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.
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9
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The Development of Neuronal Polarity: A Retrospective View. J Neurosci 2019; 38:1867-1873. [PMID: 29467146 DOI: 10.1523/jneurosci.1372-16.2018] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 01/04/2018] [Accepted: 01/05/2018] [Indexed: 11/21/2022] Open
Abstract
In 1988, Carlos Dotti, Chris Sullivan, and I published a paper on the establishment of polarity by hippocampal neurons in culture, which continues to be frequently cited 30 years later (Dotti et al., 1988). By following individual neurons from the time of plating until they had formed well developed axonal and dendritic arbors, we identified the five stages of development that lead to the mature expression of neuronal polarity. We were surprised to find that, before axon formation, the cells pass through a multipolar phase, in which several, apparently identical short neurites undergo periods of extension and retraction. Then one of these neurites begins a period of prolonged growth, becoming the definitive axon; the remaining neurites subsequently become dendrites. This observation suggested that any of the initial neurites were capable of becoming axons, a hypothesis confirmed by later work. In this Progressions article, I will try to recall the circumstances that led to this work, recapture some of the challenges we faced in conducting these experiments, and consider why some of today's neuroscientists still find this paper relevant.
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10
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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.
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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
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11
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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.
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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
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12
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Stanganello E, Zahavi EE, Burute M, Smits J, Jordens I, Maurice MM, Kapitein LC, Hoogenraad CC. Wnt Signaling Directs Neuronal Polarity and Axonal Growth. iScience 2019; 13:318-327. [PMID: 30878878 PMCID: PMC6423405 DOI: 10.1016/j.isci.2019.02.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 09/18/2018] [Accepted: 02/26/2019] [Indexed: 11/19/2022] Open
Abstract
The establishment of neuronal polarity is driven by cytoskeletal remodeling that stabilizes and promotes the growth of a single axon from one of the multiple neurites. The importance of the local microtubule stabilization in this process has been revealed however, the external signals initiating the cytoskeletal rearrangements are not completely understood. In this study, we show that local activation of the canonical Wnt pathway regulates neuronal polarity and axonal outgrowth. We found that in the early stages of neuronal polarization, Wnt3a accumulates in one of the neurites of unpolarized cells and thereby could determine axon positioning. Subsequently, Wnt3a localizes to the growing axon, where it activates the canonical Wnt pathway and controls axon positioning and axonal length. We propose a model in which Wnt3a regulates the formation and growth of the axon by activating local intracellular signaling events leading to microtubule remodeling. Wnt3a distributes asymmetrically in early stages neurons A spatially localized Wnt3a source determines axon positioning and early guidance Concentration gradient of Wnt3a guides axonal outgrowth across a microfluidic chamber Wnt3a directly controls microtubules remodeling
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Affiliation(s)
- Eliana Stanganello
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Eitan Erez Zahavi
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Mithila Burute
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Jasper Smits
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Ingrid Jordens
- Oncode Institute, Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Madelon M Maurice
- Oncode Institute, Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Lukas C Kapitein
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
| | - Casper C Hoogenraad
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands.
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13
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Wang L, Bing T, Liu Y, Zhang N, Shen L, Liu X, Wang J, Shangguan D. Imaging of Neurite Network with an Anti-L1CAM Aptamer Generated by Neurite-SELEX. J Am Chem Soc 2018; 140:18066-18073. [PMID: 30485743 DOI: 10.1021/jacs.8b10783] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Neurite outgrowth is the critical step of nervous development. Molecular probes against neurites are essential for evaluation of the nervous system development, compound neurotoxicity, and drug efficacy on nerve regeneration. To obtain a neurite probe, we developed a neurite-SELEX strategy and generated a DNA aptamer, yly12, that strongly binds neurites. The molecular target of yly12 was identified to be neural cell adhesion molecule L1 (L1CAM), a surface antigen expressed in normal nervous system and various cancers. Here, yly12 was successfully applied to image the three-dimensional network of neurites between live cells, as well as the neurite fibers on normal brain tissue section. This aptamer was also found to have an inhibitory effect on neurite outgrowth between cells. Given the advantages of aptamers, yly12 hold great potential as a molecular tool in the field of neuroscientific research. The high efficiency of neurite-SELEX suggests that SELEX against a subcellular structure instead of the whole cells is more effective in obtaining the desired aptamers.
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Affiliation(s)
- Linlin Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Tao Bing
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Ying Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Nan Zhang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Luyao Shen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Xiangjun Liu
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Junyan Wang
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
| | - Dihua Shangguan
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Analytical Chemistry for Living Biosystems, CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.,University of the Chinese Academy of Sciences , Beijing 100049 , China
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14
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Oelz DB, Del Castillo U, Gelfand VI, Mogilner A. Microtubule Dynamics, Kinesin-1 Sliding, and Dynein Action Drive Growth of Cell Processes. Biophys J 2018; 115:1614-1624. [PMID: 30268540 PMCID: PMC6260207 DOI: 10.1016/j.bpj.2018.08.046] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 05/14/2018] [Accepted: 08/30/2018] [Indexed: 01/08/2023] Open
Abstract
Recent experimental studies of the role of microtubule sliding in neurite outgrowth suggested a qualitative model, according to which kinesin-1 motors push the minus-end-out microtubules against the cell membrane and generate the early cell processes. At the later stage, dynein takes over the sliding, expels the minus-end-out microtubules from the neurites, and pulls in the plus-end-out microtubules that continue to elongate the nascent axon. This model leaves unanswered a number of questions: why is dynein unable to generate the processes alone, whereas kinesin-1 can? What is the role of microtubule dynamics in process initiation and growth? Can the model correctly predict the rates of process growth in control and dynein-inhibited cases? What triggers the transition from kinesin-driven to dynein-driven sliding? To answer these questions, we combine computational modeling of a network of elastic dynamic microtubules and kinesin-1 and dynein motors with measurements of the process growth kinetics and pharmacological perturbations in Drosophila S2 cells. The results verify quantitatively the qualitative model of the microtubule polarity sorting and suggest that dynein-powered elongation is effective only when the processes are longer than a threshold length, which explains why kinesin-1 alone, but not dynein, is sufficient for the process growth. Furthermore, we show that the mechanism of process elongation depends critically on microtubule dynamic instability. Both modeling and experimental measurements show, surprisingly, that dynein inhibition accelerates the process extension. We discuss implications of the model for the general problems of cell polarization, cytoskeletal polarity emergence, and cell process protrusion.
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Affiliation(s)
- Dietmar B Oelz
- School of Mathematics and Physics, The University of Queensland, Brisbane, Australia
| | - Urko Del Castillo
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Evanston, Illinois
| | - Vladimir I Gelfand
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Evanston, Illinois
| | - Alex Mogilner
- Courant Institute of Mathematical Sciences and Department of Biology, New York University, New York City, New York.
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15
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Abstract
Each neuron forms a single axon and multiple dendrites, and this configuration is important for wiring the brain. How only a single axon extends from a neuron, however, remains unknown. This study demonstrates that CAMSAP3, a protein that binds the minus-end of microtubules, preferentially localizes along axons in hippocampal neurons. Remarkably, mutations of CAMSAP3 lead to production of multiple axons in these neurons. In attempts to uncover mechanisms underlying this abnormal axon extension, the authors found that CAMSAP3-anchored microtubules escape from acetylation, a process mediated by α-tubulin acetyltransferase-1, and depletion of this enzyme abolishes abnormal axon formation in CAMSAP3 mutants. These findings reveal that CAMSAP3 controls microtubule dynamics, preventing tubulin acetylation; this mechanism is required for single-axon formation. The molecular mechanisms that guide each neuron to become polarized, forming a single axon and multiple dendrites, remain unknown. Here we show that CAMSAP3 (calmodulin-regulated spectrin-associated protein 3), a protein that regulates the minus-end dynamics of microtubules, plays a key role in maintaining neuronal polarity. In mouse hippocampal neurons, CAMSAP3 was enriched in axons. Although axonal microtubules were generally acetylated, CAMSAP3 was preferentially localized along a less-acetylated fraction of the microtubules. CAMSAP3-mutated neurons often exhibited supernumerary axons, along with an increased number of neurites having nocodazole-resistant/acetylated microtubules compared with wild-type neurons. Analysis using cell lines showed that CAMSAP3 depletion promoted tubulin acetylation, and conversely, mild overexpression of CAMSAP3 inhibited it, suggesting that CAMSAP3 works to retain nonacetylated microtubules. In contrast, CAMSAP2, a protein related to CAMSAP3, was detected along all neurites, and its loss did not affect neuronal polarity, nor did it cause increased tubulin acetylation. Depletion of α-tubulin acetyltransferase-1 (αTAT1), the key enzyme for tubulin acetylation, abolished CAMSAP3 loss-dependent multiple-axon formation. These observations suggest that CAMSAP3 sustains a nonacetylated pool of microtubules in axons, interfering with the action of αTAT1, and this process is important to maintain neuronal polarity.
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16
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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.
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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.
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17
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Iuliano O, Yoshimura A, Prospéri MT, Martin R, Knölker HJ, Coudrier E. Myosin 1b promotes axon formation by regulating actin wave propagation and growth cone dynamics. J Cell Biol 2018; 217:2033-2046. [PMID: 29588377 PMCID: PMC5987710 DOI: 10.1083/jcb.201703205] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 12/20/2017] [Accepted: 03/02/2018] [Indexed: 02/06/2023] Open
Abstract
Single-headed myosin 1 has been identified in neurons, but its function in these cells is still unclear. We demonstrate that depletion of myosin 1b (Myo1b), inhibition of its motor activity, or its binding to phosphoinositides impairs the formation of the axon, whereas overexpression of Myo1b increases the number of axon-like structures. Myo1b is associated with growth cones and actin waves, two major contributors to neuronal symmetry breaking. We show that Myo1b controls the dynamics of the growth cones and the anterograde propagation of the actin waves. By coupling the membrane to the actin cytoskeleton, Myo1b regulates the size of the actin network as well as the stability and size of filopodia in the growth cones. Our data provide the first evidence that a myosin 1 plays a major role in neuronal symmetry breaking and argue for a mechanical control of the actin cytoskeleton both in actin waves and in the growth cones by this myosin.
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Affiliation(s)
- Olga Iuliano
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR 144, Paris, France
| | - Azumi Yoshimura
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR 144, Paris, France
| | - Marie-Thérèse Prospéri
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR 144, Paris, France
| | - René Martin
- Department of Chemistry, Technische Univesität Dresden, Dresden, Germany
| | | | - Evelyne Coudrier
- Institut Curie, Paris Sciences et Lettres Research University, Centre National de la Recherche Scientifique, UMR 144, Paris, France
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18
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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]
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19
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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.
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20
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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.
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21
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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.
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22
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Cytoskeletal Symmetry Breaking and Chirality: From Reconstituted Systems to Animal Development. Symmetry (Basel) 2015. [DOI: 10.3390/sym7042062] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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23
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Abstract
Neurons are highly polarized cells with structurally and functionally distinct processes called axons and dendrites. This polarization underlies the directional flow of information in the central nervous system, so the establishment and maintenance of neuronal polarization is crucial for correct development and function. Great progress in our understanding of how neurons establish their polarity has been made through the use of cultured hippocampal neurons, while recent technological advances have enabled in vivo analysis of axon specification and elongation. This short review and accompanying poster highlight recent advances in this fascinating field, with an emphasis on the signaling mechanisms underlying axon and dendrite specification in vitro and in vivo.
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Affiliation(s)
- Tetsuya Takano
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Chundi Xu
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Yasuhiro Funahashi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Takashi Namba
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Kozo Kaibuchi
- Department of Cell Pharmacology, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
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24
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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.
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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
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25
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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: 51] [Impact Index Per Article: 5.7] [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.
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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
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26
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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
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27
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Sakakibara A, Hatanaka Y. Neuronal polarization in the developing cerebral cortex. Front Neurosci 2015; 9:116. [PMID: 25904841 PMCID: PMC4389351 DOI: 10.3389/fnins.2015.00116] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/22/2015] [Indexed: 12/17/2022] Open
Abstract
Cortical neurons consist of excitatory projection neurons and inhibitory GABAergic interneurons, whose connections construct highly organized neuronal circuits that control higher order information processing. Recent progress in live imaging has allowed us to examine how these neurons differentiate during development in vivo or in in vivo-like conditions. These analyses have revealed how the initial steps of polarization, in which neurons establish an axon, occur. Interestingly, both excitatory and inhibitory cortical neurons establish neuronal polarity de novo by undergoing a multipolar stage reminiscent of the manner in which polarity formation occurs in hippocampal neurons in dissociated culture. In this review, we focus on polarity formation in cortical neurons and describe their typical morphology and dynamic behavior during the polarization period. We also discuss cellular and molecular mechanisms underlying polarization, with reference to polarity formation in dissociated hippocampal neurons in vitro.
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Affiliation(s)
- Akira Sakakibara
- College of Life and Health Sciences, Chubu University Kasugai, Japan
| | - Yumiko Hatanaka
- Division of Cerebral Circuitry, National Institute for Physiological Sciences Okazaki, Japan ; Japan Science and Technology Agency, Core Research for Evolutional Science and Technology Tokyo, Japan
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28
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Karunarathne WKA, O'Neill PR, Gautam N. Subcellular optogenetics - controlling signaling and single-cell behavior. J Cell Sci 2014; 128:15-25. [PMID: 25433038 DOI: 10.1242/jcs.154435] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Variation in signaling activity across a cell plays a crucial role in processes such as cell migration. Signaling activity specific to organelles within a cell also likely plays a key role in regulating cellular functions. To understand how such spatially confined signaling within a cell regulates cell behavior, tools that exert experimental control over subcellular signaling activity are required. Here, we discuss the advantages of using optogenetic approaches to achieve this control. We focus on a set of optical triggers that allow subcellular control over signaling through the activation of G-protein-coupled receptors (GPCRs), receptor tyrosine kinases and downstream signaling proteins, as well as those that inhibit endogenous signaling proteins. We also discuss the specific insights with regard to signaling and cell behavior that these subcellular optogenetic approaches can provide.
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Affiliation(s)
- W K Ajith Karunarathne
- Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA
| | - Patrick R O'Neill
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Narasimhan Gautam
- Department of Anesthesiology, Washington University School of Medicine, St Louis, MO 63110, USA Department of Genetics, Washington University School of Medicine, St Louis, MO 63110, USA
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29
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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.
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Affiliation(s)
- Chin-Lin Guo
- Institute of Physics, Academia Sinica, Taipei, 11529, Taiwan
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30
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Optically triggering spatiotemporally confined GPCR activity in a cell and programming neurite initiation and extension. Proc Natl Acad Sci U S A 2013; 110:E1565-74. [PMID: 23479634 DOI: 10.1073/pnas.1220697110] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
G-protein-coupled receptor (GPCR) activity gradients evoke important cell behavior but there is a dearth of methods to induce such asymmetric signaling in a cell. Here we achieved reversible, rapidly switchable patterns of spatiotemporally restricted GPCR activity in a single cell. We recruited properties of nonrhodopsin opsins--rapid deactivation, distinct spectral tuning, and resistance to bleaching--to activate native Gi, Gq, or Gs signaling in selected regions of a cell. Optical inputs were designed to spatiotemporally control levels of second messengers, IP3, phosphatidylinositol (3,4,5)-triphosphate, and cAMP in a cell. Spectrally selective imaging was accomplished to simultaneously monitor optically evoked molecular and cellular response dynamics. We show that localized optical activation of an opsin-based trigger can induce neurite initiation, phosphatidylinositol (3,4,5)-triphosphate increase, and actin remodeling. Serial optical inputs to neurite tips can refashion early neuron differentiation. Methods here can be widely applied to program GPCR-mediated cell behaviors.
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31
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Chau AH, Walter JM, Gerardin J, Tang C, Lim WA. Designing synthetic regulatory networks capable of self-organizing cell polarization. Cell 2012; 151:320-32. [PMID: 23039994 DOI: 10.1016/j.cell.2012.08.040] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2012] [Revised: 07/07/2012] [Accepted: 08/16/2012] [Indexed: 11/26/2022]
Abstract
How cells form global, self-organized structures using genetically encoded molecular rules remains elusive. Here, we take a synthetic biology approach to investigate the design principles governing cell polarization. First, using a coarse-grained computational model, we searched for all possible simple networks that can achieve polarization. All solutions contained one of three minimal motifs: positive feedback, mutual inhibition, or inhibitor with positive feedback. These minimal motifs alone could achieve polarization under limited conditions; circuits that combined two or more of these motifs were significantly more robust. With these design principles as a blueprint, we experimentally constructed artificial polarization networks in yeast, using a toolkit of chimeric signaling proteins that spatially direct the synthesis and degradation of phosphatidylinositol (3,4,5)-trisphosphate (PIP(3)). Circuits with combinatorial motifs yielded clear foci of synthetic PIP(3) that can persist for nearly an hour. Thus, by harnessing localization-regulated signaling molecules, we can engineer simple molecular circuits that reliably execute spatial self-organized programs.
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Affiliation(s)
- Angela H Chau
- Howard Hughes Medical Institute and Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA
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32
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Mogilner A, Allard J, Wollman R. Cell polarity: quantitative modeling as a tool in cell biology. Science 2012; 336:175-9. [PMID: 22499937 DOI: 10.1126/science.1216380] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Among a number of innovative approaches that have modernized cell biology, modeling has a prominent yet unusual place. One popular view is that we progress linearly, from conceptual to ever more detailed models. We review recent discoveries of cell polarity mechanisms, in which modeling played an important role, to demonstrate that the experiment-theory feedback loop requires diverse models characterized by varying levels of biological detail and mathematical complexity. We argue that a quantitative model is a tool that has to fit an experimental study, and the model's value should be judged not by how complex and detailed it is, but by what could be learned from it.
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Affiliation(s)
- Alex Mogilner
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA 95616, USA.
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Hatanaka Y, Yamauchi K, Murakami F. Formation of Axon-dendrite polarity in situ: Initiation of axons from polarized and non-polarized cells. Dev Growth Differ 2012; 54:398-407. [DOI: 10.1111/j.1440-169x.2012.01344.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Kenta Yamauchi
- Laboratory of Neuroscience, Graduate School of Frontier Biosciences; Osaka University; Suita, Osaka 565-0871; Japan
| | - Fujio Murakami
- Laboratory of Neuroscience, Graduate School of Frontier Biosciences; Osaka University; Suita, Osaka 565-0871; Japan
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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: 65] [Impact Index Per Article: 5.4] [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.
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Affiliation(s)
- Yumiko Hatanaka
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan.
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