1
|
Frumento D, Ţălu Ș. Light-based technologies in immunotherapy: advances, mechanisms and applications. Immunotherapy 2025; 17:123-131. [PMID: 40032620 PMCID: PMC11901425 DOI: 10.1080/1750743x.2025.2470111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2024] [Accepted: 02/18/2025] [Indexed: 03/05/2025] Open
Abstract
Light-based immunotherapy uses specific wavelengths of light to activate or modulate immune responses. It primarily employs two mechanisms: direct activation of immune cells and indirect modulation of the tumor microenvironment (TME). Several light-based technologies are under investigation or clinical use in immunotherapy, including photodynamic immunotherapy (PDIT) and photothermal therapy (PTT). Optogenetic tools have the potential to precisely control T-cell receptor activation, cytokine release, or the activity of other immune effector cells. Light-based technologies present innovative opportunities within the realm of immunotherapy. The ability to precisely regulate immune cell activation via optogenetics, alongside the improved targeting of cancer cells through photoimmunotherapy, signifies a transformative shift in our strategies for immune modulation. Although many of these technologies remain in the experimental stage for various applications, initial findings are encouraging, especially concerning cancer treatment and immune modulation. Continued research and clinical trials are essential to fully harness the capabilities of light technology in the context of immune cell therapy.
Collapse
Affiliation(s)
| | - Ștefan Ţălu
- The Directorate of Research, Development and Innovation Management (DMCDI), The Technical University of Cluj-Napoca, Cluj-Napoca, Romania
| |
Collapse
|
2
|
Zhuang Z, Meng Y, Xue Y, Wang Y, Cheng X, Jing J. Adaptation of STIM1 structure-function relationships for optogenetic control of calcium signaling. J Biol Chem 2024; 300:107636. [PMID: 39122007 PMCID: PMC11402311 DOI: 10.1016/j.jbc.2024.107636] [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: 03/12/2024] [Revised: 07/26/2024] [Accepted: 07/30/2024] [Indexed: 08/12/2024] Open
Abstract
In cellular contexts, the oscillation of calcium ions (Ca2+) is intricately linked to various physiological processes, such as cell proliferation, metabolism, and survival. Stromal interaction molecule 1 (STIM1) proteins form a crucial regulatory component in the store-operated calcium entry process. The structural attributes of STIM1 are vital for its functionality, encompassing distinct domains situated in the endoplasmic reticulum lumen and the cytoplasm. The intraluminal domain enables the timely detection of diminishing Ca2+ concentrations, prompting structural modifications that activate the cytoplasmic domain. This activated cytoplasmic domain undergoes conformational alterations and engages with membrane components, opening a channel that facilitates the influx of Ca2+ from the extracellular environment. Given its multiple domains and interaction mechanisms, STIM1 plays a foundational role in cellular biology. This review focuses on the design of optogenetic tools inspired by the structure and function of STIM1. These tools offer a groundbreaking approach for studying and manipulating intracellular Ca2+ signaling with precise spatiotemporal control. We further explore the practical applications of these tools, spanning fundamental scientific research, clinical studies, and their potential for translational research.
Collapse
Affiliation(s)
- Zirui Zhuang
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, Zhejiang, China; School of Molecular Medicine, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences (UCAS), Hangzhou, China
| | - Yuxin Meng
- College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou, China
| | - Yu Xue
- School of Life Science, Tianjin University, Tianjin, China
| | - Yan Wang
- Collaborative Innovation Center of Yangtza River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Hangzhou, China
| | - Xiangdong Cheng
- Department of Gastric Surgery, Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HlM), Chinese Academy of Sciences, Hangzhou, Zhejiang, China; Zhejiang Key Laboratory of Prevention, Diagnosis and Therapy of Upper Gastrointestinal Cancer, Hangzhou, China; Zhejiang Provincial Research Center for Upper Gastrointestinal Tract Cancer, Zhejiang Cancer Hospital, Hangzhou, China
| | - Ji Jing
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Zhejiang Cancer Hospital, Hangzhou, Zhejiang, China; Department of Gastric Surgery, Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HlM), Chinese Academy of Sciences, Hangzhou, Zhejiang, China.
| |
Collapse
|
3
|
Zhao P, Ding X, Li L, Jiang G. A review of cell-type specific circuit mechanisms underlying epilepsy. ACTA EPILEPTOLOGICA 2024; 6:18. [PMID: 40217549 PMCID: PMC11960342 DOI: 10.1186/s42494-024-00159-2] [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: 01/12/2024] [Accepted: 03/21/2024] [Indexed: 04/14/2025] Open
Abstract
Epilepsy is a prevalent neurological disorder, yet its underlying mechanisms remain incompletely understood. Accumulated studies have indicated that epilepsy is characterized by abnormal neural circuits. Understanding the circuit mechanisms is crucial for comprehending the pathogenesis of epilepsy. With advances in tracing and modulating tools for neural circuits, some epileptic circuits have been uncovered. This comprehensive review focuses on the circuit mechanisms underlying epilepsy in various neuronal subtypes, elucidating their distinct roles. Epileptic seizures are primarily characterized by the hyperactivity of glutamatergic neurons and inhibition of GABAergic neurons. However, specific activated GABAergic neurons and suppressed glutamatergic neurons exacerbate epilepsy through preferentially regulating the activity of GABAergic neurons within epileptic circuits. Distinct subtypes of GABAergic neurons contribute differently to epileptic activities, potentially due to their diverse connection patterns. Moreover, identical GABAergic neurons may assume distinct roles in different stages of epilepsy. Both GABAergic neurons and glutamatergic neurons with long-range projecting fibers innervate multiple nuclei; nevertheless, not all of these circuits contribute to epileptic activities. Epileptic circuits originating from the same nuclei may display diverse contributions to epileptic activities, and certain glutamatergic circuits from the same nuclei may even exert opposing effects on epilepsy. Neuromodulatory neurons, including cholinergic, serotonergic, dopaminergic, and noradrenergic neurons, are also implicated in epilepsy, although the underlying circuit mechanisms remain poorly understood. These studies suggest that epileptic nuclei establish intricate connections through cell-type-specific circuits and play pivotal roles in epilepsy. However, there are still limitations in knowledge and methods, and further understanding of epileptic circuits is crucial, particularly in the context of refractory epilepsy.
Collapse
Affiliation(s)
- Peilin Zhao
- Institute of Neurological Diseases, Affiliated Hospital of Clinical School of Medicine, North Sichuan Medical College, Nanchong, Sichuan, 637000, China
- Nanomedicine Innovation Research and Development Transformation Institute, Affiliated Hospital of Clinical School of Medicine, North Sichuan Medical College, Nanchong, Sichuan, 637000, China
| | - Xiaomi Ding
- Institute of Neurological Diseases, Affiliated Hospital of Clinical School of Medicine, North Sichuan Medical College, Nanchong, Sichuan, 637000, China
| | - Lini Li
- Institute of Neurological Diseases, Affiliated Hospital of Clinical School of Medicine, North Sichuan Medical College, Nanchong, Sichuan, 637000, China
| | - Guohui Jiang
- Institute of Neurological Diseases, Affiliated Hospital of Clinical School of Medicine, North Sichuan Medical College, Nanchong, Sichuan, 637000, China.
- Department of Neurology, Affiliated Hospital of Clinical School of Medicine, North Sichuan Medical College, Nanchong, Sichuan, 637000, China.
| |
Collapse
|
4
|
Verma K, Kumar S. How Do We Connect Brain Areas with Cognitive Functions? The Past, the Present and the Future. NEUROSCI 2022; 3:521-532. [PMID: 39483437 PMCID: PMC11523709 DOI: 10.3390/neurosci3030037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 09/12/2022] [Indexed: 11/03/2024] Open
Abstract
One of the central goals of cognitive neuroscience is to understand how structure relates to function. Over the past century, clinical studies on patients with lesions have provided key insights into the relationship between brain areas and behavior. Since the early efforts for characterization of cognitive functions focused on localization, we provide an account of cognitive function in terms of localization. Next, using body perception as an example, we summarize the contemporary techniques. Finally, we outline the trajectory of current progress into the future and discuss the implications for clinical and basic neuroscience.
Collapse
Affiliation(s)
- Khushboo Verma
- Department of Neurology, Dell Medical School, The University of Texas, Austin, TX 78712, USA
| | - Satwant Kumar
- Center for Perceptual Systems, University of Texas, Austin, TX 78712, USA
| |
Collapse
|
5
|
Dai R, Yu T, Weng D, Li H, Cui Y, Wu Z, Guo Q, Zou H, Wu W, Gao X, Qi Z, Ren Y, Wang S, Li Y, Luo M. A neuropsin-based optogenetic tool for precise control of G q signaling. SCIENCE CHINA. LIFE SCIENCES 2022; 65:1271-1284. [PMID: 35579776 DOI: 10.1007/s11427-022-2122-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 04/29/2022] [Indexed: 06/15/2023]
Abstract
Gq-coupled receptors regulate numerous physiological processes by activating enzymes and inducing intracellular Ca2+ signals. There is a strong need for an optogenetic tool that enables powerful experimental control over Gq signaling. Here, we present chicken opsin 5 (cOpn5) as the long sought-after, single-component optogenetic tool that mediates ultra-sensitive optical control of intracellular Gq signaling with high temporal and spatial resolution. Expressing cOpn5 in HEK 293T cells and primary mouse astrocytes enables blue light-triggered, Gq-dependent Ca2+ release from intracellular stores and protein kinase C activation. Strong Ca2+ transients were evoked by brief light pulses of merely 10 ms duration and at 3 orders lower light intensity of that for common optogenetic tools. Photostimulation of cOpn5-expressing cells at the subcellular and single-cell levels generated fast intracellular Ca2+ transition, thus demonstrating the high spatial precision of cOpn5 optogenetics. The cOpn5-mediated optogenetics could also be applied to activate neurons and control animal behavior in a circuit-dependent manner. cOpn5 optogenetics may find broad applications in studying the mechanisms and functional relevance of Gq signaling in both non-excitable cells and excitable cells in all major organ systems.
Collapse
Affiliation(s)
- Ruicheng Dai
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- School of Life Sciences, Peking University, Beijing, 100871, China
- Peking University-Tsinghua University-NIBS Joint Graduate Program, NIBS, Beijing, 102206, China
| | - Tao Yu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- Peking University-Tsinghua University-NIBS Joint Graduate Program, NIBS, Beijing, 102206, China
| | - Danwei Weng
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- Graduate School of Peking Union Medical College, Beijing, 100730, China
| | - Heng Li
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- Tsinghua Institute of Multidisciplinary Biomedical Research (TIMBR), Beijing, 102206, China
| | - Yuting Cui
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Zhaofa Wu
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, 100871, China
- PKU-McGovern Institute for Brain Research, Beijing, 100871, China
| | - Qingchun Guo
- Chinese Institute for Brain Research, Beijing, 102206, China
- Capital Medical University, Beijing, 102206, China
| | - Haiyue Zou
- Chinese Institute for Brain Research, Beijing, 102206, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Wenting Wu
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
- Peking University-Tsinghua University-NIBS Joint Graduate Program, NIBS, Beijing, 102206, China
| | - Xinwei Gao
- Chinese Institute for Brain Research, Beijing, 102206, China
| | - Zhongyang Qi
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Yuqi Ren
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China
| | - Shu Wang
- Chinese Institute for Brain Research, Beijing, 102206, China
| | - Yulong Li
- State Key Laboratory of Membrane Biology, Peking University School of Life Sciences, Beijing, 100871, China
- PKU-McGovern Institute for Brain Research, Beijing, 100871, China
| | - Minmin Luo
- National Institute of Biological Sciences (NIBS), Beijing, 102206, China.
- Graduate School of Peking Union Medical College, Beijing, 100730, China.
- Chinese Institute for Brain Research, Beijing, 102206, China.
- Tsinghua Institute of Multidisciplinary Biomedical Research (TIMBR), Beijing, 102206, China.
| |
Collapse
|
6
|
Provansal M, Marazova K, Sahel JA, Picaud S. Vision Restoration by Optogenetic Therapy and Developments Toward Sonogenetic Therapy. Transl Vis Sci Technol 2022; 11:18. [PMID: 35024784 PMCID: PMC8762673 DOI: 10.1167/tvst.11.1.18] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 12/22/2021] [Indexed: 11/24/2022] Open
Abstract
After revolutionizing neuroscience, optogenetic therapy has entered successfully in clinical trials for restoring vision to blind people with degenerative eye diseases, such as retinitis pigmentosa. These clinical trials still have to evaluate the visual acuity achieved by patients and to determine if it reaches its theoretical limit extrapolated from ex vivo experiments. Different strategies are developed in parallel to reduce required light levels and improve information processing by targeting various cell types. For patients with vision loss due to optic atrophy, as in the case of glaucoma, optogenetic cortical stimulation is hampered by light absorption and scattering by the brain tissue. By contrast, ultrasound waves can diffuse widely through the dura mater and the brain tissue as indicated by ultrasound imaging. Based on our recent results in rodents, we propose the sonogenetic therapy relying on activation of the mechanosensitive channel as a very promising vision restoration strategy with a suitable spatiotemporal resolution. Genomic approaches may thus provide efficient brain machine interfaces for sight restoration.
Collapse
Affiliation(s)
| | - Katia Marazova
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - José Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Centre Hospitalier National d'Ophtalmologie des XV-XX, Paris, France
| | - Serge Picaud
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| |
Collapse
|
7
|
Karapinar R, Schwitalla JC, Eickelbeck D, Pakusch J, Mücher B, Grömmke M, Surdin T, Knöpfel T, Mark MD, Siveke I, Herlitze S. Reverse optogenetics of G protein signaling by zebrafish non-visual opsin Opn7b for synchronization of neuronal networks. Nat Commun 2021; 12:4488. [PMID: 34301944 PMCID: PMC8302595 DOI: 10.1038/s41467-021-24718-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 06/24/2021] [Indexed: 01/15/2023] Open
Abstract
Opn7b is a non-visual G protein-coupled receptor expressed in zebrafish. Here we find that Opn7b expressed in HEK cells constitutively activates the Gi/o pathway and illumination with blue/green light inactivates G protein-coupled inwardly rectifying potassium channels. This suggests that light acts as an inverse agonist for Opn7b and can be used as an optogenetic tool to inhibit neuronal networks in the dark and interrupt constitutive inhibition in the light. Consistent with this prediction, illumination of recombinant expressed Opn7b in cortical pyramidal cells results in increased neuronal activity. In awake mice, light stimulation of Opn7b expressed in pyramidal cells of somatosensory cortex reliably induces generalized epileptiform activity within a short (<10 s) delay after onset of stimulation. Our study demonstrates a reversed mechanism for G protein-coupled receptor control and Opn7b as a tool for controlling neural circuit properties.
Collapse
Affiliation(s)
- Raziye Karapinar
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
- Laboratory of Optogenetics and Circuit Neuroscience, Imperial College London, London, UK
- The Francis Crick Institute, London, UK
| | | | - Dennis Eickelbeck
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
- Laboratory of Optogenetics and Circuit Neuroscience, Imperial College London, London, UK
- The Francis Crick Institute, London, UK
| | - Johanna Pakusch
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, Germany
| | - Brix Mücher
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Michelle Grömmke
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, Germany
| | - Tatjana Surdin
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Thomas Knöpfel
- Laboratory of Optogenetics and Circuit Neuroscience, Imperial College London, London, UK
| | - Melanie D Mark
- Behavioral Neuroscience, Ruhr-University Bochum, Bochum, Germany.
| | - Ida Siveke
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
- German Cancer Consortium (DKTK/DKFZ), West German Cancer Center, University Hospital Essen, Essen, Germany
| | - Stefan Herlitze
- Department of Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany.
| |
Collapse
|
8
|
Eickelbeck D, Rudack T, Tennigkeit SA, Surdin T, Karapinar R, Schwitalla JC, Mücher B, Shulman M, Scherlo M, Althoff P, Mark MD, Gerwert K, Herlitze S. Lamprey Parapinopsin ("UVLamP"): a Bistable UV-Sensitive Optogenetic Switch for Ultrafast Control of GPCR Pathways. Chembiochem 2019; 21:612-617. [PMID: 31468691 PMCID: PMC7079062 DOI: 10.1002/cbic.201900485] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Indexed: 12/17/2022]
Abstract
Optogenetics uses light‐sensitive proteins, so‐called optogenetic tools, for highly precise spatiotemporal control of cellular states and signals. The major limitations of such tools include the overlap of excitation spectra, phototoxicity, and lack of sensitivity. The protein characterized in this study, the Japanese lamprey parapinopsin, which we named UVLamP, is a promising optogenetic tool to overcome these limitations. Using a hybrid strategy combining molecular, cellular, electrophysiological, and computational methods we elucidated a structural model of the dark state and probed the optogenetic potential of UVLamP. Interestingly, it is the first described bistable vertebrate opsin that has a charged amino acid interacting with the Schiff base in the dark state, that has no relevance for its photoreaction. UVLamP is a bistable UV‐sensitive opsin that allows for precise and sustained optogenetic control of G protein‐coupled receptor (GPCR) pathways and can be switched on, but more importantly also off within milliseconds via lowintensity short light pulses. UVLamP exhibits an extremely narrow excitation spectrum in the UV range allowing for sustained activation of the Gi/o pathway with a millisecond UV light pulse. Its sustained pathway activation can be switched off, surprisingly also with a millisecond blue light pulse, minimizing phototoxicity. Thus, UVLamP serves as a minimally invasive, narrow‐bandwidth probe for controlling the Gi/o pathway, allowing for combinatorial use with multiple optogenetic tools or sensors. Because UVLamP activated Gi/o signals are generally inhibitory and decrease cellular activity, it has tremendous potential for health‐related applications such as relieving pain, blocking seizures, and delaying neurodegeneration.
Collapse
Affiliation(s)
- Dennis Eickelbeck
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Till Rudack
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Stefan Alexander Tennigkeit
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Tatjana Surdin
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Raziye Karapinar
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Jan-Claudius Schwitalla
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Brix Mücher
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Maiia Shulman
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Marvin Scherlo
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Philipp Althoff
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Melanie D Mark
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| | - Klaus Gerwert
- Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, Gesundheitscampus 4, 44801, Bochum, Germany.,Department of Biophysics, Ruhr University Bochum, ND04/596, Universitätsstrasse 150, 44780, Bochum, Germany
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, Ruhr University Bochum, ND7/31, Universitätsstasse 150, 44780, Bochum, Germany
| |
Collapse
|
9
|
Weiss LC. Sensory Ecology of Predator-Induced Phenotypic Plasticity. Front Behav Neurosci 2019; 12:330. [PMID: 30713490 PMCID: PMC6345714 DOI: 10.3389/fnbeh.2018.00330] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Accepted: 12/13/2018] [Indexed: 12/12/2022] Open
Abstract
Ecological communities are organized in trophic levels that share manifold interactions forming complex food webs. Infochemicals can further modify these interactions, e.g., by inducing defenses in prey. The micro-crustacean Daphnia is able to respond to predator-specific chemical cues indicating an increased predation risk. Daphnia shows plastic responses by adapting its morphology, behavior, and physiology, increasing organism, and population fitness. This stabilizes community structures. This review will describe the progress that has been made in understanding the high degree of plasticity observed in the model crustacean Daphnia. I summarize current knowledge on the processes of predator detection, ranging from the nature of biologically active chemical cues to the underlying neurophysiological mechanisms. With this, I aim to provide a comprehensive overview on the molecular mechanisms of ad hoc environmental phenotypic adaptation. In times of climate change and pollution understanding information transfer in aquatic systems is valuable as it will allow us to predict whether and how community structures are being affected.
Collapse
Affiliation(s)
- Linda C. Weiss
- Department of Animal Ecology, Evolution and Biodiversity, Ruhr University Bochum, Bochum, Germany
| |
Collapse
|
10
|
Ronzitti E, Emiliani V, Papagiakoumou E. Methods for Three-Dimensional All-Optical Manipulation of Neural Circuits. Front Cell Neurosci 2018; 12:469. [PMID: 30618626 PMCID: PMC6304748 DOI: 10.3389/fncel.2018.00469] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 11/19/2018] [Indexed: 12/18/2022] Open
Abstract
Optical means for modulating and monitoring neuronal activity, have provided substantial insights to neurophysiology and toward our understanding of how the brain works. Optogenetic actuators, calcium or voltage imaging probes and other molecular tools, combined with advanced microscopies have allowed an "all-optical" readout and modulation of neural circuits. Completion of this remarkable work is evolving toward a three-dimensional (3D) manipulation of neural ensembles at a high spatiotemporal resolution. Recently, original optical methods have been proposed for both activating and monitoring neurons in a 3D space, mainly through optogenetic compounds. Here, we review these methods and anticipate possible combinations among them.
Collapse
Affiliation(s)
| | | | - Eirini Papagiakoumou
- Wavefront Engineering Microscopy Group, Photonics Department, Institut de la Vision, Sorbonne Université, Inserm S968, CNRS UMR7210, Paris, France
| |
Collapse
|
11
|
Garita-Hernandez M, Guibbal L, Toualbi L, Routet F, Chaffiol A, Winckler C, Harinquet M, Robert C, Fouquet S, Bellow S, Sahel JA, Goureau O, Duebel J, Dalkara D. Optogenetic Light Sensors in Human Retinal Organoids. Front Neurosci 2018; 12:789. [PMID: 30450028 PMCID: PMC6224345 DOI: 10.3389/fnins.2018.00789] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 10/12/2018] [Indexed: 01/26/2023] Open
Abstract
Optogenetic technologies paved the way to dissect complex neural circuits and monitor neural activity using light in animals. In retinal disease, optogenetics has been used as a therapeutic modality to reanimate the retina after the loss of photoreceptor outer segments. However, it is not clear today which ones of the great diversity of microbial opsins are best suited for therapeutic applications in human retinas as cell lines, primary cell cultures and animal models do not predict expression patterns of microbial opsins in human retinal cells. Therefore, we sought to generate retinal organoids derived from human induced pluripotent stem cells (hiPSCs) as a screening tool to explore the membrane trafficking efficacy of some recently described microbial opsins. We tested both depolarizing and hyperpolarizing microbial opsins including CatCh, ChrimsonR, ReaChR, eNpHR 3.0, and Jaws. The membrane localization of eNpHR 3.0, ReaChR, and Jaws was the highest, likely due to their additional endoplasmic reticulum (ER) release and membrane trafficking signals. In the case of opsins that were not engineered to improve trafficking efficiency in mammalian cells such as CatCh and ChrimsonR, membrane localization was less efficient. Protein accumulation in organelles such as ER and Golgi was observed at high doses with CatCh and ER retention lead to an unfolded protein response. Also, cytoplasmic localization was observed at high doses of ChrimsonR. Our results collectively suggest that retinal organoids derived from hiPSCs can be used to predict the subcellular fate of optogenetic proteins in a human retinal context. Such organoids are also versatile tools to validate other gene therapy products and drug molecules.
Collapse
Affiliation(s)
| | - Laure Guibbal
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Lyes Toualbi
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Fiona Routet
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Antoine Chaffiol
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Celine Winckler
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Marylin Harinquet
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Camille Robert
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Stephane Fouquet
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | | | - José-Alain Sahel
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Olivier Goureau
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Jens Duebel
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| | - Deniz Dalkara
- Institut de la Vision, Sorbonne Université, INSERM, CNRS, Paris, France
| |
Collapse
|
12
|
Mark MD, Donner M, Eickelbeck D, Stepien J, Nowrousian M, Kück U, Paris F, Hellinger J, Herlitze S. Visual tuning in the flashlight fish Anomalops katoptron to detect blue, bioluminescent light. PLoS One 2018; 13:e0198765. [PMID: 29995896 PMCID: PMC6040694 DOI: 10.1371/journal.pone.0198765] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 05/24/2018] [Indexed: 01/23/2023] Open
Abstract
Bioluminescence is a fascinating phenomenon and can be found in many different organisms including fish. It has been suggested that bioluminescence is used for example for defense, prey attraction, and for intraspecific communication to attract for example sexual partners. The flashlight fish, Anomalops katoptron (A. katoptron), is a nocturnal fish that produces bioluminescence and lives in shallow waters, which makes it ideal for laboratory studies. In order to understand A. katoptron's ability to detect bioluminescent light (480 to 490 nm) at night, we characterized the visual system adaptation of A. katoptron using phylogenetic, electrophysiological and behavioral studies. We found that the retinae of A. katoptron contain rods and sparse cones. A. katoptron retinae express two main visual pigments, rhodopsin (RH1), and to a lesser extent, rhodopsin-like opsin (RH2). Interestingly, recombinant RH1 and RH2 are maximally sensitive to a wavelength of approximately 490 nm light (λmax), which correspond to the spectral peak of in vivo electroretinogram (ERG) measurements. In addition, behavioral assays revealed that A. katoptron is attracted by low intensity blue but not red light. Collectively, our results suggest that the A. katoptron visual system is optimized to detect blue light in the frequency range of its own bioluminescence and residual starlight.
Collapse
Affiliation(s)
- Melanie D. Mark
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
- * E-mail:
| | - Marcel Donner
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Dennis Eickelbeck
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Jennifer Stepien
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Minou Nowrousian
- Department of General and Molecular Botany, Ruhr-University Bochum, Bochum, Germany
| | - Ulrich Kück
- Department of General and Molecular Botany, Ruhr-University Bochum, Bochum, Germany
| | - Frank Paris
- Department of Animal Physiology, Ruhr-University Bochum, Bochum, Germany
| | - Jens Hellinger
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, Ruhr-University Bochum, Bochum, Germany
| |
Collapse
|
13
|
Chaffiol A, Duebel J. Mini-Review: Cell Type-Specific Optogenetic Vision Restoration Approaches. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1074:69-73. [DOI: 10.1007/978-3-319-75402-4_9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
14
|
Sengupta A, Chaffiol A, Macé E, Caplette R, Desrosiers M, Lampič M, Forster V, Marre O, Lin JY, Sahel JA, Picaud S, Dalkara D, Duebel J. Red-shifted channelrhodopsin stimulation restores light responses in blind mice, macaque retina, and human retina. EMBO Mol Med 2016; 8:1248-1264. [PMID: 27679671 PMCID: PMC5090658 DOI: 10.15252/emmm.201505699] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 08/09/2016] [Accepted: 08/11/2016] [Indexed: 01/31/2023] Open
Abstract
Targeting the photosensitive ion channel channelrhodopsin-2 (ChR2) to the retinal circuitry downstream of photoreceptors holds promise in treating vision loss caused by retinal degeneration. However, the high intensity of blue light necessary to activate channelrhodopsin-2 exceeds the safety threshold of retinal illumination because of its strong potential to induce photochemical damage. In contrast, the damage potential of red-shifted light is vastly lower than that of blue light. Here, we show that a red-shifted channelrhodopsin (ReaChR), delivered by AAV injections in blind rd1 mice, enables restoration of light responses at the retinal, cortical, and behavioral levels, using orange light at intensities below the safety threshold for the human retina. We further show that postmortem macaque retinae infected with AAV-ReaChR can respond with spike trains to orange light at safe intensities. Finally, to directly address the question of translatability to human subjects, we demonstrate for the first time, AAV- and lentivirus-mediated optogenetic spike responses in ganglion cells of the postmortem human retina.
Collapse
Affiliation(s)
- Abhishek Sengupta
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Antoine Chaffiol
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Emilie Macé
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Romain Caplette
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Mélissa Desrosiers
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Maruša Lampič
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Valérie Forster
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Olivier Marre
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - John Y Lin
- School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - José-Alain Sahel
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
- Hôpital des Quinze-Vingts, Paris, France
| | - Serge Picaud
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Deniz Dalkara
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| | - Jens Duebel
- INSERM U968, Paris, France
- Sorbonne Universités UPMC Univ Paris 06 UMR_S 968 Institut de la Vision, Paris, France
- CNRS UMR_7210, Paris, France
| |
Collapse
|
15
|
Spoida K, Eickelbeck D, Karapinar R, Eckhardt T, Mark MD, Jancke D, Ehinger BV, König P, Dalkara D, Herlitze S, Masseck OA. Melanopsin Variants as Intrinsic Optogenetic On and Off Switches for Transient versus Sustained Activation of G Protein Pathways. Curr Biol 2016; 26:1206-12. [PMID: 27068418 DOI: 10.1016/j.cub.2016.03.007] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 02/09/2016] [Accepted: 03/01/2016] [Indexed: 10/22/2022]
Abstract
G-protein-coupled receptors (GPCRs) represent the major protein family for cellular modulation in mammals. Therefore, various strategies have been developed to analyze the function of GPCRs involving pharmaco- and optogenetic approaches [1, 2]. However, a tool that combines precise control of the activation and deactivation of GPCR pathways and/or neuronal firing with limited phototoxicity is still missing. We compared the biophysical properties and optogenetic application of a human and a mouse melanopsin variant (hOpn4L and mOpn4L) on the control of Gi/o and Gq pathways in heterologous expression systems and mouse brain. We found that GPCR pathways can be switched on/off by blue/yellow light. The proteins differ in their kinetics and wavelength dependence to activate and deactivate G protein pathways. Whereas mOpn4L is maximally activated by very short light pulses, leading to sustained G protein activation, G protein responses of hOpn4L need longer light pulses to be activated and decline in amplitude. Based on the different biophysical properties, brief light activation of mOpn4L is sufficient to induce sustained neuronal firing in cerebellar Purkinje cells (PC), whereas brief light activation of hOpn4L induces AP firing, which declines in frequency over time. Most importantly, mOpn4L-induced sustained firing can be switched off by yellow light. Based on the biophysical properties, hOpn4L and mOpn4L represent the first GPCR optogenetic tools, which can be used to switch GPCR pathways/neuronal firing on an off with temporal precision and limited phototoxicity. We suggest to name these tools moMo and huMo for future optogenetic applications.
Collapse
Affiliation(s)
- Katharina Spoida
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Dennis Eickelbeck
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Raziye Karapinar
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Tobias Eckhardt
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Melanie D Mark
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Dirk Jancke
- Optical Imaging Group, Institut für Neuroinformatik, NB 2/27, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Benedikt Valerian Ehinger
- Institute of Cognitive Science, University of Osnabrück, Albrechtstrasse 28, 49076 Osnabrück, Germany
| | - Peter König
- Institute of Cognitive Science, University of Osnabrück, Albrechtstrasse 28, 49076 Osnabrück, Germany; Department of Neurophysiology and Pathophysiology, University Medical Center Hamburg Eppendorf, 20246 Hamburg, Germany
| | - Deniz Dalkara
- Sorbonne Universités, UPMC University Paris 06, INSERM, CNRS, Institut de la Vision, 17 Rue Moreau, 75012 Paris, France
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
| | - Olivia A Masseck
- Department of General Zoology and Neurobiology, ND 7/31, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| |
Collapse
|
16
|
Urban P, Kirchner SR, Mühlbauer C, Lohmüller T, Feldmann J. Reversible control of current across lipid membranes by local heating. Sci Rep 2016; 6:22686. [PMID: 26940847 PMCID: PMC4778043 DOI: 10.1038/srep22686] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 02/18/2016] [Indexed: 12/17/2022] Open
Abstract
Lipid membranes are almost impermeable for charged molecules and ions that can pass the membrane barrier only with the help of specialized transport proteins. Here, we report how temperature manipulation at the nanoscale can be employed to reversibly control the electrical resistance and the amount of current that flows through a bilayer membrane with pA resolution. For this experiment, heating is achieved by irradiating gold nanoparticles that are attached to the bilayer membrane with laser light at their plasmon resonance frequency. We found that controlling the temperature on the nanoscale renders it possible to reproducibly regulate the current across a phospholipid membrane and the membrane of living cells in absence of any ion channels.
Collapse
Affiliation(s)
- Patrick Urban
- Photonics and Optoelectronics Group, Department of Physics and Center for NanoScience (CeNS), LMU Munich, Amalienstraße 54, Munich, 80799, Germany
| | - Silke R Kirchner
- Photonics and Optoelectronics Group, Department of Physics and Center for NanoScience (CeNS), LMU Munich, Amalienstraße 54, Munich, 80799, Germany
| | - Christian Mühlbauer
- Photonics and Optoelectronics Group, Department of Physics and Center for NanoScience (CeNS), LMU Munich, Amalienstraße 54, Munich, 80799, Germany
| | - Theobald Lohmüller
- Photonics and Optoelectronics Group, Department of Physics and Center for NanoScience (CeNS), LMU Munich, Amalienstraße 54, Munich, 80799, Germany.,Nanosystems Initiative Munich (NIM), Schellingstraße 4, 80539 Munich, Germany
| | - Jochen Feldmann
- Photonics and Optoelectronics Group, Department of Physics and Center for NanoScience (CeNS), LMU Munich, Amalienstraße 54, Munich, 80799, Germany.,Nanosystems Initiative Munich (NIM), Schellingstraße 4, 80539 Munich, Germany
| |
Collapse
|
17
|
Abstract
PURPOSE OF REVIEW In this review, we will discuss the recent developments in optogenetics and their potential applications in ophthalmology to restore vision in retinal degenerative diseases. RECENT FINDINGS In recent years, we have seen major advances in the field of optogenetics, providing us with novel opsins for potential applications in the retina. Microbial opsins with improved light sensitivity and red-shifted action spectra allow optogenetic stimulation at light levels well below the safety threshold in the human eye. In parallel, remarkable success in the development of highly efficient viral vectors for ocular gene therapy led to new strategies of using these novel optogenetic tools for vision restoration. SUMMARY These recent findings show that novel optogenetic tools and viral vectors for ocular gene delivery are now available providing many opportunities to develop potential optogenetic strategies for vision restoration.
Collapse
Affiliation(s)
- Jens Duebel
- Institut de la Vision
Université Pierre et Marie Curie - Paris 6 - UM80Institut National de la Santé et de la Recherche Médicale - U968Centre National de la Recherche Scientifique - UMR721017 Rue Moreau, 75012 Paris
| | - Katia Marazova
- Institut de la Vision
Université Pierre et Marie Curie - Paris 6 - UM80Institut National de la Santé et de la Recherche Médicale - U968Centre National de la Recherche Scientifique - UMR721017 Rue Moreau, 75012 Paris
| | - José-Alain Sahel
- Institut de la Vision
Université Pierre et Marie Curie - Paris 6 - UM80Institut National de la Santé et de la Recherche Médicale - U968Centre National de la Recherche Scientifique - UMR721017 Rue Moreau, 75012 Paris
- Fondation Ophtalmologique Rothschild
75019 Paris
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts
INSERM-DHOS CIC 1423 -
- Institute of Ophthalmology [London]
University College of London [London] - London EC1V 9EL
| |
Collapse
|
18
|
Optogenetics applications for treating spinal cord injury. Asian Spine J 2015; 9:299-305. [PMID: 25901246 PMCID: PMC4404549 DOI: 10.4184/asj.2015.9.2.299] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 11/08/2014] [Accepted: 11/16/2014] [Indexed: 12/28/2022] Open
Abstract
Cases of spinal cord injury (SCI) are increasing all over the world; and in USA alone, there are 273,000 patients, which not only leads to morbidity and mortality but also results in a great economic burden. Many approaches are being used at the pre-clinical and clinical level to treat SCI including therapeutic agents, surgical decompression, stem cell therapy etc. Recently, a new approach called optogenetics has emerged in which light sensitive proteins are used to switch neurons on and off, and this approach has great potential to be used as therapy due to its specificity and rapid response in milliseconds. Few animal studies have been performed so far in which the respiratory and bladder function of rats was restored through the use of optogenetics. On the basis of promising results obtained, in the future, this approach can prove to be a valuable tool to treat patients with SCI.
Collapse
|
19
|
Masseck OA, Spoida K, Dalkara D, Maejima T, Rubelowski JM, Wallhorn L, Deneris ES, Herlitze S. Vertebrate cone opsins enable sustained and highly sensitive rapid control of Gi/o signaling in anxiety circuitry. Neuron 2014; 81:1263-1273. [PMID: 24656249 DOI: 10.1016/j.neuron.2014.01.041] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
G protein-coupled receptors (GPCRs) coupling to Gi/o signaling pathways are involved in the control of important physiological functions, which are difficult to investigate because of the limitation of tools to control the signaling pathway with precise kinetics and specificity. We established two vertebrate cone opsins, short- and long-wavelength opsin, for long-lasting and repetitive activation of Gi/o signaling pathways in vitro and in vivo. We demonstrate for both opsins the repetitive fast, membrane-delimited, ultra light-sensitive, and wavelength-dependent activation of the Gi/o pathway in HEK cells. We also show repetitive control of Gi/o pathway activation in 5-HT1A receptor domains in the dorsal raphe nucleus (DRN) in brain slices and in vivo, which is sufficient to modulate anxiety behavior in mice. Thus, vertebrate cone opsins represent a class of tools for understanding the role of Gi/o-coupled GPCRs in health and disease.
Collapse
Affiliation(s)
- Olivia A Masseck
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Katharina Spoida
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Deniz Dalkara
- INSERM, U968, Sorbonne Universités, UPMC Univ Paris 06, UMR_S 968, CNRS, UMR_7210 Institut de la Vision, Paris, F-75012, France
| | - Takashi Maejima
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Johanna M Rubelowski
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Lutz Wallhorn
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Evan S Deneris
- Department of Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Stefan Herlitze
- Department of General Zoology and Neurobiology, ND7/31, Ruhr-University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
| |
Collapse
|
20
|
Maejima T, Masseck OA, Mark MD, Herlitze S. Modulation of firing and synaptic transmission of serotonergic neurons by intrinsic G protein-coupled receptors and ion channels. Front Integr Neurosci 2013; 7:40. [PMID: 23734105 PMCID: PMC3661940 DOI: 10.3389/fnint.2013.00040] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 05/03/2013] [Indexed: 11/13/2022] Open
Abstract
Serotonergic neurons project to virtually all regions of the central nervous system and are consequently involved in many critical physiological functions such as mood, sexual behavior, feeding, sleep/wake cycle, memory, cognition, blood pressure regulation, breathing, and reproductive success. Therefore, serotonin release and serotonergic neuronal activity have to be precisely controlled and modulated by interacting brain circuits to adapt to specific emotional and environmental states. We will review the current knowledge about G protein-coupled receptors and ion channels involved in the regulation of serotonergic system, how their regulation is modulating the intrinsic activity of serotonergic neurons and its transmitter release and will discuss the latest methods for controlling the modulation of serotonin release and intracellular signaling in serotonergic neurons in vitro and in vivo.
Collapse
Affiliation(s)
- Takashi Maejima
- Department of Zoology and Neurobiology, Ruhr-University Bochum Bochum, Germany
| | | | | | | |
Collapse
|
21
|
Egawa R, Hososhima S, Hou X, Katow H, Ishizuka T, Nakamura H, Yawo H. Optogenetic probing and manipulation of the calyx-type presynaptic terminal in the embryonic chick ciliary ganglion. PLoS One 2013; 8:e59179. [PMID: 23555628 PMCID: PMC3605445 DOI: 10.1371/journal.pone.0059179] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 02/12/2013] [Indexed: 11/23/2022] Open
Abstract
The calyx-type synapse of chick ciliary ganglion (CG) has been intensively studied for decades as a model system for the synaptic development, morphology and physiology. Despite recent advances in optogenetics probing and/or manipulation of the elementary steps of the transmitter release such as membrane depolarization and Ca2+ elevation, the current gene-manipulating methods are not suitable for targeting specifically the calyx-type presynaptic terminals. Here, we evaluated a method for manipulating the molecular and functional organization of the presynaptic terminals of this model synapse. We transfected progenitors of the Edinger-Westphal (EW) nucleus neurons with an EGFP expression vector by in ovo electroporation at embryonic day 2 (E2) and examined the CG at E8–14. We found that dozens of the calyx-type presynaptic terminals and axons were selectively labeled with EGFP fluorescence. When a Brainbow construct containing the membrane-tethered fluorescent proteins m-CFP, m-YFP and m-RFP, was introduced together with a Cre expression construct, the color coding of each presynaptic axon facilitated discrimination among inter-tangled projections, particularly during the developmental re-organization period of synaptic connections. With the simultaneous expression of one of the chimeric variants of channelrhodopsins, channelrhodopsin-fast receiver (ChRFR), and R-GECO1, a red-shifted fluorescent Ca2+-sensor, the Ca2+ elevation was optically measured under direct photostimulation of the presynaptic terminal. Although this optically evoked Ca2+ elevation was mostly dependent on the action potential, a significant component remained even in the absence of extracellular Ca2+. It is suggested that the photo-activation of ChRFR facilitated the release of Ca2+ from intracellular Ca2+ stores directly or indirectly. The above system, by facilitating the molecular study of the calyx-type presynaptic terminal, would provide an experimental platform for unveiling the molecular mechanisms underlying the morphology, physiology and development of synapses.
Collapse
Affiliation(s)
- Ryo Egawa
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Japan Science and Technology Agency (JST), Core Research of Evolutional Science & Technology (CREST), Tokyo, Japan
- Tohoku University Institute for International Advanced Research and Education, Sendai, Japan
| | - Shoko Hososhima
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Japan Science and Technology Agency (JST), Core Research of Evolutional Science & Technology (CREST), Tokyo, Japan
| | - Xubin Hou
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Department of Molecular Neurobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Hidetaka Katow
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Japan Science and Technology Agency (JST), Core Research of Evolutional Science & Technology (CREST), Tokyo, Japan
| | - Toru Ishizuka
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Japan Science and Technology Agency (JST), Core Research of Evolutional Science & Technology (CREST), Tokyo, Japan
| | - Harukazu Nakamura
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Department of Molecular Neurobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan
| | - Hiromu Yawo
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai, Japan
- Japan Science and Technology Agency (JST), Core Research of Evolutional Science & Technology (CREST), Tokyo, Japan
- Center for Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan
- * E-mail:
| |
Collapse
|
22
|
Deardorff AS, Romer SH, Deng Z, Bullinger KL, Nardelli P, Cope TC, Fyffe REW. Expression of postsynaptic Ca2+-activated K+ (SK) channels at C-bouton synapses in mammalian lumbar -motoneurons. J Physiol 2013; 591:875-97. [PMID: 23129791 PMCID: PMC3591704 DOI: 10.1113/jphysiol.2012.240879] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 10/31/2012] [Indexed: 01/27/2023] Open
Abstract
Small-conductance calcium-activated potassium (SK) channels mediate medium after-hyperpolarization (AHP) conductances in neurons throughout the central nervous system. However, the expression profile and subcellular localization of different SK channel isoforms in lumbar spinal α-motoneurons (α-MNs) is unknown. Using immunohistochemical labelling of rat, mouse and cat spinal cord, we reveal a differential and overlapping expression of SK2 and SK3 isoforms across specific types of α-MNs. In rodents, SK2 is expressed in all α-MNs, whereas SK3 is expressed preferentially in small-diameter α-MNs; in cats, SK3 is expressed in all α-MNs. Function-specific expression of SK3 was explored using post hoc immunostaining of electrophysiologically characterized rat α-MNs in vivo. These studies revealed strong relationships between SK3 expression and medium AHP properties. Motoneurons with SK3-immunoreactivity exhibit significantly longer AHP half-decay times (24.67 vs. 11.02 ms) and greater AHP amplitudes (3.27 vs. 1.56 mV) than MNs lacking SK3-immunoreactivity. We conclude that the differential expression of SK isoforms in rat and mouse spinal cord may contribute to the range of medium AHP durations across specific MN functional types and may be a molecular factor distinguishing between slow- and fast-type α-MNs in rodents. Furthermore, our results show that SK2- and SK3-immunoreactivity is enriched in distinct postsynaptic domains that contain Kv2.1 channel clusters associated with cholinergic C-boutons on the soma and proximal dendrites of α-MNs. We suggest that this remarkably specific subcellular membrane localization of SK channels is likely to represent the basis for a cholinergic mechanism for effective regulation of channel function and cell excitability.
Collapse
Affiliation(s)
- Adam S Deardorff
- Department of Neuroscience, Cell Biology & Physiology, Wright State University, Boonshoft School of Medicine, Dayton, OH 45435, USA
| | | | | | | | | | | | | |
Collapse
|
23
|
|
24
|
Saint Clair EC, Ogren JI, Mamaev S, Russano D, Kralj JM, Rothschild KJ. Near-IR resonance Raman spectroscopy of archaerhodopsin 3: effects of transmembrane potential. J Phys Chem B 2012. [PMID: 23189985 DOI: 10.1021/jp309996a] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Archaerhodopsin 3 (AR3) is a light driven proton pump from Halorubrum sodomense that has been used as a genetically targetable neuronal silencer and an effective fluorescent sensor of transmembrane potential. Unlike the more extensively studied bacteriorhodopsin (BR) from Halobacterium salinarum, AR3 readily incorporates into the plasma membrane of both E. coli and mammalian cells. Here, we used near-IR resonance Raman confocal microscopy to study the effects of pH and membrane potential on the AR3 retinal chromophore structure. Measurements were performed both on AR3 reconstituted into E. coli polar lipids and in vivo in E. coli expressing AR3 in the absence and presence of a negative transmembrane potential. The retinal chromophore structure of AR3 is in an all-trans configuration almost identical to BR over the entire pH range from 3 to 11. Small changes are detected in the retinal ethylenic stretching frequency and Schiff Base (SB) hydrogen bonding strength relative to BR which may be related to a different water structure near the SB. In the case of the AR3 mutant D95N, at neutral pH an all-trans retinal O-like species (O(all-trans)) is found. At higher pH a second 13-cis retinal N-like species (N(13-cis)) is detected which is attributed to a slowly decaying intermediate in the red-light photocycle of D95N. However, the amount of N(13-cis) detected is less in E. coli cells but is restored upon addition of carbonyl cyanide m-chlorophenyl hydrazone (CCCP) or sonication, both of which dissipate the normal negative membrane potential. We postulate that these changes are due to the effect of membrane potential on the N(13-cis) to M(13-cis) levels accumulated in the D95N red-light photocycle and on a molecular level by the effects of the electric field on the protonation/deprotonation of the cytoplasmic accessible SB. This mechanism also provides a possible explanation for the observed fluorescence dependence of AR3 and other microbial rhodopsins on transmembrane potential.
Collapse
Affiliation(s)
- Erica C Saint Clair
- Department of Physics, Photonics Center and Molecular Biophysics Laboratory, Boston University, Boston, Massachusetts 02215, USA
| | | | | | | | | | | |
Collapse
|
25
|
Treatments to restore respiratory function after spinal cord injury and their implications for regeneration, plasticity and adaptation. Exp Neurol 2011; 235:18-25. [PMID: 22200541 DOI: 10.1016/j.expneurol.2011.12.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Revised: 11/18/2011] [Accepted: 12/09/2011] [Indexed: 02/04/2023]
Abstract
Spinal cord injury (SCI) often leads to impaired breathing. In most cases, such severe respiratory complications lead to morbidity and death. However, in the last few years there has been extensive work examining ways to restore this vital function after experimental spinal cord injury. In addition to finding strategies to rescue breathing activity, many of these experiments have also yielded a great deal of information about the innate plasticity and capacity for adaptation in the respiratory system and its associated circuitry in the spinal cord. This review article will highlight experimental SCI resulting in compromised breathing, the various methods of restoring function after such injury, and some recent findings from our own laboratory. Additionally, it will discuss findings about motor and CNS respiratory plasticity and adaptation with potential clinical and translational implications.
Collapse
|
26
|
Abstract
A significant challenge for neuroscientists is to determine how both electrical and chemical signals affect the activity of cells and circuits and how the nervous system subsequently translates that activity into behavior. Remote, bidirectional manipulation of those signals with high spatiotemporal precision is an ideal approach to addressing that challenge. Neuroscientists have recently developed a diverse set of tools that permit such experimental manipulation with varying degrees of spatial, temporal, and directional control. These tools use light, peptides, and small molecules to primarily activate ion channels and G protein-coupled receptors (GPCRs) that in turn activate or inhibit neuronal firing. By monitoring the electrophysiological, biochemical, and behavioral effects of such activation/inhibition, researchers can better understand the links between brain activity and behavior. Here, we review the tools that are available for this type of experimentation. We describe the development of the tools and highlight exciting in vivo data. We focus primarily on designer GPCRs (receptors activated solely by synthetic ligands, designer receptors exclusively activated by designer drugs) and microbial opsins (e.g., channelrhodopsin-2, halorhodopsin, Volvox carteri channelrhodopsin) but also describe other novel techniques that use orthogonal receptors, caged ligands, allosteric modulators, and other approaches. These tools differ in the direction of their effect (activation/inhibition, hyperpolarization/depolarization), their onset and offset kinetics (milliseconds/minutes/hours), the degree of spatial resolution they afford, and their invasiveness. Although none of these tools is perfect, each has advantages and disadvantages, which we describe, and they are all still works in progress. We conclude with suggestions for improving upon the existing tools.
Collapse
Affiliation(s)
- Sarah C Rogan
- University of North Carolina School of Medicine, Department of Pharmacology, 120 Mason Farm Rd, Chapel Hill, NC 27514, USA
| | | |
Collapse
|
27
|
Störtkuhl KF, Fiala A. The Smell of Blue Light: A New Approach toward Understanding an Olfactory Neuronal Network. Front Neurosci 2011; 5:72. [PMID: 21647413 PMCID: PMC3103046 DOI: 10.3389/fnins.2011.00072] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 05/06/2011] [Indexed: 11/13/2022] Open
Abstract
Olfaction is one of the most important senses throughout the animal kingdom. It enables animals to discriminate between a wide variety of attractive and repulsive odorants and often plays a decisive role in species specific communication. In recent years the analysis of olfactory systems both invertebrates and invertebrates has attracted much scientific interest. In this context a pivotal question is how the properties and connectivities of individual neurons contribute to a functioning neuronal network that mediates odor-guided behavior. As a novel approach to analyze the role of individual neurons within a circuitry, techniques have been established that make use of light-sensitive proteins. In this review we introduce a non-invasive, optogenetic technique which was used to manipulate the activity of individual neurons in the olfactory system of Drosophila melanogaster larvae. Both channelrhodopsin-2 and the photosensitive adenylyl cyclase PAC α in individual olfactory receptor neurons (ORNs) of the olfactory system of Drosophila larvae allows stimulating individual receptor neurons by light. Depending on which particular ORN is optogenetically activated, repulsion or attraction behavior can be induced, indicating which sensory neurons underlie which type of behavior.
Collapse
Affiliation(s)
- Klemens F Störtkuhl
- AG Physiology of Senses, Department of Biology and Biotechnology, Ruhr University Bochum Bochum, Germany
| | | |
Collapse
|
28
|
Hofmann B, Maybeck V, Eick S, Meffert S, Ingebrandt S, Wood P, Bamberg E, Offenhäusser A. Light induced stimulation and delay of cardiac activity. LAB ON A CHIP 2010; 10:2588-2596. [PMID: 20689860 DOI: 10.1039/c003091k] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This article shows the combination of light activatable ion channels and microelectrode array (MEA) technology for bidirectionally interfacing cells. HL-1 cultures, a mouse derived cardiomyocyte-like cell line, transfected with channelrhodopsin were stimulated with a microscope coupled 473 nm laser and recorded with custom built 64 electrode MEAs. Channelrhodopsin induced depolarization of the cell can evoke action potentials (APs) in single cells. Spreading of the AP over the cell layer can then be measured with good spatiotemporal resolution using MEA recordings. The possibility for light induced pacemaker switching in cultures was shown. Furthermore, the suppression of APs can also be achieved with the laser. Possible applications include cell analysis, e.g. pacemaker interference or induced pacemaker switching, and medical applications such as a combined cardiac pacemaker and defibrillator triggered by light. Since current prosthesis research focuses on bidirectionality, this system may be applied to any electrogenic cell, including neurons or muscles, to advance this field.
Collapse
Affiliation(s)
- Boris Hofmann
- Institute of Bio- and Nanosystems-Bioelectronics (IBN-2) and Jara-FIT, Forschungszentrum Jülich, Leo-Brandt-Str., D-52425 Jülich, Germany
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Janovjak H, Szobota S, Wyart C, Trauner D, Isacoff EY. A light-gated, potassium-selective glutamate receptor for the optical inhibition of neuronal firing. Nat Neurosci 2010; 13:1027-32. [PMID: 20581843 PMCID: PMC2915903 DOI: 10.1038/nn.2589] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Accepted: 05/26/2010] [Indexed: 12/12/2022]
Abstract
Genetically targeted light-activated ion channels and pumps make it possible to determine the role of specific neurons in neuronal circuits, information processing and behavior. We developed a K+-selective ionotropic glutamate receptor that reversibly inhibits neuronal activity in response to light in dissociated neurons and brain slice and also reversibly suppresses behavior in zebrafish. The receptor is a chimera of the pore region of a K+-selective bacterial glutamate receptor and the ligand-binding domain of a light-gated mammalian kainate receptor. This hyperpolarizing light-gated channel, HyLighter, is turned on by a brief light pulse at one wavelength and turned off by a pulse at a second wavelength. The control is obtained at moderate intensity. After optical activation, the photocurrent and optical silencing of activity persists in the dark for extended periods. The low light requirement and bi-stability of HyLighter represent advantages for the dissection of neural circuitry.
Collapse
Affiliation(s)
- Harald Janovjak
- Department of Molecular and Cell Biology and Helen Wills Neuroscience Institute, University of California, Berkeley, California, USA
| | | | | | | | | |
Collapse
|
30
|
Oh E, Maejima T, Liu C, Deneris E, Herlitze S. Substitution of 5-HT1A receptor signaling by a light-activated G protein-coupled receptor. J Biol Chem 2010; 285:30825-36. [PMID: 20643652 DOI: 10.1074/jbc.m110.147298] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Understanding serotonergic (5-HT) signaling is critical for understanding human physiology, behavior, and neuropsychiatric disease. 5-HT mediates its actions via ionotropic and metabotropic 5-HT receptors. The 5-HT(1A) receptor is a metabotropic G protein-coupled receptor linked to the G(i/o) signaling pathway and has been specifically implicated in the pathogenesis of depression and anxiety. To understand and precisely control 5-HT(1A) signaling, we created a light-activated G protein-coupled receptor that targets into 5-HT(1A) receptor domains and substitutes for endogenous 5-HT(1A) receptors. To induce 5-HT(1A)-like targeting, vertebrate rhodopsin was tagged with the C-terminal domain (CT) of 5-HT(1A) (Rh-CT(5-HT1A)). Rh-CT(5-HT1A) activates G protein-coupled inward rectifying K(+) channels in response to light and causes membrane hyperpolarization in hippocampal neurons, similar to the agonist-induced responses of the 5-HT(1A) receptor. The intracellular distribution of Rh-CT(5-HT1A) resembles that of the 5-HT(1A) receptor; Rh-CT(5-HT1A) localizes to somatodendritic sites and is efficiently trafficked to distal dendritic processes. Additionally, neuronal expression of Rh-CT(5-HT1A), but not Rh, decreases 5-HT(1A) agonist sensitivity, suggesting that Rh-CT(5-HT1A) and 5-HT(1A) receptors compete to interact with the same trafficking machinery. Finally, Rh-CT(5-HT1A) is able to rescue 5-HT(1A) signaling of 5-HT(1A) KO mice in cultured neurons and in slices of the dorsal raphe showing that Rh-CT(5-HT1A) is able to functionally compensate for native 5-HT(1A). Thus, as an optogenetic tool, Rh-CT(5-HT1A) has the potential to directly correlate in vivo 5-HT(1A) signaling with 5-HT neuron activity and behavior in both normal animals and animal models of neuropsychiatric disease.
Collapse
Affiliation(s)
- Eugene Oh
- Department of Neurosciences, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | | | | | | | | |
Collapse
|
31
|
Alilain WJ, Silver J. Shedding light on restoring respiratory function after spinal cord injury. Front Mol Neurosci 2009; 2:18. [PMID: 19893756 PMCID: PMC2773153 DOI: 10.3389/neuro.02.018.2009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Accepted: 10/01/2009] [Indexed: 11/13/2022] Open
Abstract
Loss of respiratory function is one of the leading causes of death following spinal cord injury. Because of this, much work has been done in studying ways to restore respiratory function following spinal cord injury (SCI) – including pharmacological and regeneration strategies. With the emergence of new and powerful tools from molecular neuroscience, new therapeutically relevant alternatives to these approaches have become available, including expression of light sensitive proteins called channelrhodopsins. In this article we briefly review the history of various attempts to restore breathing after C2 hemisection, and focus on our recent work using the activation of light sensitive channels to restore respiratory function after experimental SCI. We also discuss how such light-induced activity can help shed light on the inner workings of the central nervous system respiratory circuitry that controls diaphragmatic function.
Collapse
Affiliation(s)
- Warren J Alilain
- Department of Neurosciences, Case Western Reserve University School of Medicine Cleveland, OH, USA
| | | |
Collapse
|
32
|
Hodge JJL. Ion channels to inactivate neurons in Drosophila. Front Mol Neurosci 2009; 2:13. [PMID: 19750193 PMCID: PMC2741205 DOI: 10.3389/neuro.02.013.2009] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Accepted: 08/11/2009] [Indexed: 02/05/2023] Open
Abstract
Ion channels are the determinants of excitability; therefore, manipulation of their levels and properties provides an opportunity for the investigator to modulate neuronal and circuit function. There are a number of ways to suppress electrical activity in Drosophila neurons, for instance, over-expression of potassium channels (i.e. Shaker Kv1, Shaw Kv3, Kir2.1 and DORK) that are open at resting membrane potential. This will result in increased potassium efflux and membrane hyperpolarisation setting resting membrane potential below the threshold required to fire action potentials. Alternatively over-expression of other channels, pumps or co-transporters that result in a hyperpolarised membrane potential will also prevent firing. Lastly, neurons can be inactivated by, disrupting or reducing the level of functional voltage-gated sodium (Nav1 paralytic) or calcium (Cav2 cacophony) channels that mediate the depolarisation phase of action potentials. Similarly, strategies involving the opposite channel manipulation should allow net depolarisation and hyperexcitation in a given neuron. These changes in ion channel expression can be brought about by the versatile transgenic (i.e. Gal4/UAS based) systems available in Drosophila allowing fine temporal and spatial control of (channel) transgene expression. These systems are making it possible to electrically inactivate (or hyperexcite) any neuron or neural circuit in the fly brain, and much like an exquisite lesion experiment, potentially elucidate whatever interesting behaviour or phenotype each network mediates. These techniques are now being used in Drosophila to reprogram electrical activity of well-defined circuits and bring about robust and easily quantifiable changes in behaviour, allowing different models and hypotheses to be rapidly tested.
Collapse
Affiliation(s)
- James J L Hodge
- Physiology and Pharmacology Department, University of Bristol Bristol, UK
| |
Collapse
|
33
|
Sarig-Nadir O, Livnat N, Zajdman R, Shoham S, Seliktar D. Laser photoablation of guidance microchannels into hydrogels directs cell growth in three dimensions. Biophys J 2009; 96:4743-52. [PMID: 19486697 DOI: 10.1016/j.bpj.2009.03.019] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2008] [Revised: 02/10/2009] [Accepted: 03/11/2009] [Indexed: 11/27/2022] Open
Abstract
Recent years have seen rapid progress in the engineering and application of biomaterials with controlled biological, physical, and chemical properties, and the development of associated methods for micropatterning of three-dimensional tissue-engineering scaffolds. A remaining challenge is the development of robust, flexible methods that can be used to create physical guidance structures in cell-seeded scaffolds independently of environmental constraints. Here we demonstrate that focal photoablation caused by pulsed lasers can generate guidance structures in transparent hydrogels, with feature control down to the micron scale. These photopatterned microchannels guide the directional growth of neurites from dorsal root ganglia. We characterize the effect of laser properties and biomaterial properties on microchannel formation in PEGylated fibrinogen hydrogels, and the effect of photoablation on neural outgrowth. This strategy could lead to the development of a new generation of guidance channels for treating nerve injuries, and the engineering of structured three-dimensional neuronal or nonneuronal networks.
Collapse
Affiliation(s)
- Offra Sarig-Nadir
- Faculty of Biomedical Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | | | | | | | | |
Collapse
|
34
|
Abstract
Neurobiologists have long sought to understand how circuits in the nervous system are organized to generate the precise neural outputs that underlie particular behaviours. The motor circuits in the spinal cord that control locomotion, commonly referred to as central pattern generator networks, provide an experimentally tractable model system for investigating how moderately complex ensembles of neurons generate select motor behaviours. The advent of novel molecular and genetic techniques coupled with recent advances in our knowledge of spinal cord development means that a comprehensive understanding of how the motor circuitry is organized and operates may be within our grasp.
Collapse
Affiliation(s)
- Martyn Goulding
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, 10010 North Torrey Pines Road, La Jolla, California 92037, USA.
| |
Collapse
|
35
|
Sugiyama Y, Wang H, Hikima T, Sato M, Kuroda J, Takahashi T, Ishizuka T, Yawo H. Photocurrent attenuation by a single polar-to-nonpolar point mutation of channelrhodopsin-2. Photochem Photobiol Sci 2009; 8:328-36. [DOI: 10.1039/b815762f] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
36
|
Wang H, Sugiyama Y, Hikima T, Sugano E, Tomita H, Takahashi T, Ishizuka T, Yawo H. Molecular determinants differentiating photocurrent properties of two channelrhodopsins from chlamydomonas. J Biol Chem 2008; 284:5685-96. [PMID: 19103605 DOI: 10.1074/jbc.m807632200] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
A light signal is converted into an electrical one in a single molecule named channelrhodopsin, one of the archaea-type rhodopsins in unicellular green algae. Although highly homologous, two molecules of this family, channelrhodopsin-1 (ChR1) and -2 (ChR2), are distinct in photocurrent properties such as the wavelength sensitivity, desensitization, and turning-on and -off kinetics. However, the structures regulating these properties have not been completely identified. Photocurrents were analyzed for several chimera molecules made by replacing N-terminal segments of ChR2 with the homologous counterparts of ChR1. We found that the wavelength sensitivity of the photocurrent was red-shifted with negligible desensitization and slowed turning-on and -off kinetics when replacement was made with the segment containing the fifth transmembrane helix of ChR1. Therefore, this segment is involved in the determination of photocurrent properties, the wavelength sensitivity, and the kinetics characterizing ChR1 and ChR2. Eight amino acid residues differentiating this segment were exchanged one-by-one, and the photocurrent properties of each targeted mutant ChR2 were further analyzed. Among them, position Tyr(226)(ChR1)/Asn(187)(ChR2) is one of the molecular determinants involved in the wavelength sensitivity, desensitization, and turning-on and -off kinetics. It is suggested that these amino acid residues directly or indirectly interact with the chromophore as well as with the protein structure determining the photocurrent kinetics. Some of the chimera channelrhodopsins are suggested to have several advantages over the wild-type ChR2 in the introduction of light-induced membrane depolarization for the purpose of artificial stimulation of neurons in vivo and visual prosthesis for photoreceptor degeneration.
Collapse
Affiliation(s)
- Hongxia Wang
- Department of Developmental Biology and Neuroscience, Tohoku University Graduate School of Life Sciences, Sendai 980-8575, Japan
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Liang S, Yang F, Zhou C, Wang Y, Li S, Sun CK, Puglisi JL, Bers D, Sun C, Zheng J. Temperature-dependent activation of neurons by continuous near-infrared laser. Cell Biochem Biophys 2008; 53:33-42. [PMID: 19034696 DOI: 10.1007/s12013-008-9035-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2008] [Indexed: 01/28/2023]
Abstract
Optical control of neuronal activity has a number of advantages over electrical methods and can be conveniently applied to intact individual neurons in vivo. In this study, we demonstrated an experimental approach in which a focused continuous near-infrared (CNI) laser beam was used to activate single rat hippocampal neurons by transiently elevating the local temperature. Reversible changes in the amplitude and kinetics of neuronal voltage-gated Na and K channel currents were recorded following irradiation with a single-mode 980 nm CNI-laser. Using single-channel recordings under controlled temperatures as a means of calibration, it was estimated that temperature at the neuron rose by 14 degrees C in 500 ms. Computer simulation confirmed that small temperature changes of about 5 degrees C were sufficient to produce significant changes in neuronal excitability. The method should be broadly applicable to studies of neuronal activity under physiological conditions, in particular studies of temperature-sensing neurons expressing thermoTRP channels.
Collapse
Affiliation(s)
- Shanshan Liang
- Lab of Biomedical Optics, College of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116023, People's Republic of China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Alilain WJ, Li X, Horn KP, Dhingra R, Dick TE, Herlitze S, Silver J. Light-induced rescue of breathing after spinal cord injury. J Neurosci 2008; 28:11862-70. [PMID: 19005051 PMCID: PMC2615537 DOI: 10.1523/jneurosci.3378-08.2008] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2008] [Revised: 09/10/2008] [Accepted: 09/14/2008] [Indexed: 01/11/2023] Open
Abstract
Paralysis is a major consequence of spinal cord injury (SCI). After cervical SCI, respiratory deficits can result through interruption of descending presynaptic inputs to respiratory motor neurons in the spinal cord. Expression of channelrhodopsin-2 (ChR2) and photostimulation in neurons affects neuronal excitability and produces action potentials without any kind of presynaptic inputs. We hypothesized that after transducing spinal neurons in and around the phrenic motor pool to express ChR2, photostimulation would restore respiratory motor function in cervical SCI adult animals. Here we show that light activation of ChR2-expressing animals was sufficient to bring about recovery of respiratory diaphragmatic motor activity. Furthermore, robust rhythmic activity persisted long after photostimulation had ceased. This recovery was accomplished through a form of respiratory plasticity and spinal adaptation which is NMDA receptor dependent. These data suggest a novel, minimally invasive therapeutic avenue to exercise denervated circuitry and/or restore motor function after SCI.
Collapse
Affiliation(s)
| | | | | | - Rishi Dhingra
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | - Thomas E. Dick
- Department of Neurosciences and
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106
| | | | | |
Collapse
|
39
|
Schanuel SM, Bell KA, Henderson SC, McQuiston AR. Heterologous expression of the invertebrate FMRFamide-gated sodium channel as a mechanism to selectively activate mammalian neurons. Neuroscience 2008; 155:374-86. [PMID: 18598740 PMCID: PMC2600494 DOI: 10.1016/j.neuroscience.2008.05.052] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 05/30/2008] [Accepted: 05/30/2008] [Indexed: 01/01/2023]
Abstract
Considerable effort has been directed toward the development of methods to selectively activate specific subtypes of neurons. Focus has been placed on the heterologous expression of proteins that are capable of exciting neurons in which they are expressed. Here we describe the heterologous expression of the invertebrate FMRFamide (H-phenylalanine-methionine-arginine-phenylalanine-NH2) -gated sodium channel from Helix aspersa (HaFaNaC) in hippocampal slice cultures. HaFaNaC was co-expressed with a fluorescent protein (green fluorescent protein (GFP), red fluorescent protein from Discosoma sp (dsRed) or mutated form of red fluorescent protein from Discosoma sp (tdTomato)) in CA3 pyramidal neurons of rat hippocampal slice cultures using single cell electroporation. Pressure application of the agonist FMRFamide to HaFaNaC-expressing neuronal somata produced large prolonged depolarizations and bursts of action potentials (APs). FMRFamide responses were inhibited by amiloride (100 microM). In contrast, pressure application of FMRFamide to the axons of neurons expressing HaFaNaC produced no response. Fusion of GFP to the N-terminus of HaFaNaC showed that GFP-HaFaNaC was absent from axons. Bath application of FMRFamide produced persistent AP firing in HaFaNaC-expressing neurons. This FMRFamide-induced increase in the frequency of APs was dose-dependent. The concentrations of FMRFamide required to activate HaFaNaC-expressing neurons were below that required to activate the homologous acid sensing ion channel normally found in mammalian neurons. Furthermore, the mammalian neuropeptides neuropeptide FF and RFamide-related peptide-1, which have amidated RF C-termini, did not affect HaFaNaC-expressing neurons. Antagonists of NPFF receptors (BIBP3226) also had no effect on HaFaNaC. Therefore, we suggest that heterologous-expression of HaFaNaC in mammalian neurons could be a useful method to selectively and persistently excite specific subtypes of neurons in intact nervous tissue.
Collapse
Affiliation(s)
- S M Schanuel
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Box 980709, Richmond, VA 23298, USA
| | | | | | | |
Collapse
|
40
|
Abstract
Imaging and molecular approaches are perfectly suited to young, transparent zebrafish (Danio rerio), where they have allowed novel functional studies of neural circuits and their links to behavior. Here, we review cutting-edge optical and genetic techniques used to dissect neural circuits in vivo and discuss their application to future studies of developing spinal circuits using living zebrafish. We anticipate that these experiments will reveal general principles governing the assembly of neural circuits that control movements.
Collapse
Affiliation(s)
- David L McLean
- Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, USA.
| | | |
Collapse
|
41
|
Fiber-coupled light-emitting diode for localized photostimulation of neurons expressing channelrhodopsin-2. J Neurosci Methods 2008; 169:27-33. [DOI: 10.1016/j.jneumeth.2007.11.012] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2007] [Revised: 10/25/2007] [Accepted: 11/20/2007] [Indexed: 11/17/2022]
|
42
|
Ernst OP, Murcia PAS, Daldrop P, Tsunoda SP, Kateriya S, Hegemann P. Photoactivation of Channelrhodopsin. J Biol Chem 2008; 283:1637-1643. [DOI: 10.1074/jbc.m708039200] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
43
|
Abstract
Only five major types of sensory photoreceptors (BLUF-proteins, cryptochromes, phototropins, phytochromes, and rhodopsins) are used in nature to regulate developmental processes, photosynthesis, photoorientation, and control of the circadian clock. Sensory photoreceptors of algae and protists are exceptionally rich in structure and function; light-gated ion channels and photoactivated adenylate cyclases are unique examples. During the past ten years major progress has been made with respect to understanding the function, photochemistry, and structure of key sensory players of the algal kingdom.
Collapse
Affiliation(s)
- Peter Hegemann
- Institute of Biology, Experimental Biophysics, Humboldt Universität zu Berlin, 10115 Berlin, Germany.
| |
Collapse
|
44
|
Yang T, Suhail Y, Dalton S, Kernan T, Colecraft HM. Genetically encoded molecules for inducibly inactivating CaV channels. Nat Chem Biol 2007; 3:795-804. [DOI: 10.1038/nchembio.2007.42] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Accepted: 08/30/2007] [Indexed: 11/09/2022]
|
45
|
Mizuno H, Hirano T, Tagawa Y. Evidence for activity-dependent cortical wiring: formation of interhemispheric connections in neonatal mouse visual cortex requires projection neuron activity. J Neurosci 2007; 27:6760-70. [PMID: 17581963 PMCID: PMC6672694 DOI: 10.1523/jneurosci.1215-07.2007] [Citation(s) in RCA: 148] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Neuronal activity plays a pivotal role in shaping neuronal wiring. We investigated the role of neuronal activity in the formation of interhemispheric (callosal) axon projections in neonatal mouse visual cortex. Axonal labeling with enhanced green fluorescent protein (GFP) was used to demonstrate spatially organized pattern of callosal projections: GFP-labeled callosal axons from one hemisphere projected densely to a narrowly restricted region at the border between areas 17 and 18 in the contralateral hemisphere, in which they terminated in layers 1-3 and 5. This region- and layer-specific innervation pattern developed by postnatal day 15 (P15). To explore the role of neuronal activity of presynaptic and postsynaptic neurons in callosal connection development, an inwardly rectifying potassium channel, Kir2.1, was expressed in callosal projection neurons and their target postsynaptic neurons. Kir2.1 overexpression reduced the firing rate of cortical neurons. Kir2.1 overexpression in callosal projection neurons disturbed the growth of axons and their arbors that normally occurs between P7 and P13, whereas that in postsynaptic neurons had limited effect on the pattern of presynaptic callosal axon innervation. In addition, exogenous expression of a gain-of-function Kir2.1 mutant channel found in patients with a familial heart disease caused severe deficits in callosal axon projections. These results suggest that projection neuron activity plays a crucial role in interhemispheric connection development and that enhanced Kir2.1 activity can affect cortical wiring.
Collapse
Affiliation(s)
- Hidenobu Mizuno
- Department of Biophysics, Kyoto University Graduate School of Science, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan, and
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Tomoo Hirano
- Department of Biophysics, Kyoto University Graduate School of Science, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan, and
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Yoshiaki Tagawa
- Department of Biophysics, Kyoto University Graduate School of Science, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan, and
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|