1
|
Ramirez-Plascencia OD, De Luca R, Machado NLS, Eghlidi D, Khanday MA, Bandaru SS, Raffin F, Vujovic N, Arrigoni E, Saper CB. A hypothalamic circuit for circadian regulation of corticosterone secretion. RESEARCH SQUARE 2024:rs.3.rs-4718850. [PMID: 39041039 PMCID: PMC11261983 DOI: 10.21203/rs.3.rs-4718850/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
The secretion of cortisol in humans and corticosterone (Cort) in rodents follows a daily rhythm which is important in readying the individual for the daily active cycle and is impaired in chronic depression. This rhythm is orchestrated by the suprachiasmatic nucleus (SCN) which governs the activity of neurons in the paraventricular nucleus of the hypothalamus that produce the corticotropin-releasing hormone (PVHCRH neurons). The dorsomedial nucleus of the hypothalamus (DMH) serves as a crucial intermediary, being innervated by the SCN both directly and via relays in the subparaventricular zone, and projecting axons to the PVH, thereby exerting influence over the cortisol/corticosterone rhythm. However, the role and synaptic mechanisms by which DMH neurons regulate the daily rhythm of Cort secretion has not been explored. We found that either ablating or acutely inhibiting the DMH glutamatergic (DMHVglut2) neurons resulted in a 40-70% reduction in the daily peak of Cort. Deletion of the Vglut2 gene within the DMH produced a similar effect, highlighting the indispensable role of glutamatergic signaling. Chemogenetic stimulation of DMHVglut2 neurons led to an increase of Cort levels, and optogenetic activation of their terminals in the PVH in hypothalamic slices directly activated PVHCRH neurons through glutamate release (the DMHVglut2 → PVHCRH pathway). Similarly, ablating, inhibiting, or disrupting GABA transmission by DMH GABAergic (DMHVgat) neurons diminished the circadian peak of Cort, particularly under constant darkness conditions. Chemogenetic stimulation of DMHVgat neurons increased Cort, although with a lower magnitude compared to DMHVglut2 neuron stimulation, suggesting a role in disinhibiting PVHCRH neurons. Supporting this hypothesis, we found that rostral DMHVgat neurons project directly to GABAergic neurons in the caudal ventral part of the PVH and adjacent peri-PVH area (cvPVH), which directly inhibit PVHCRH neurons, and that activating the DMHVgat terminals in the cvPVH in brain slices reduced GABAergic afferent input onto the PVHCRH neurons. Finally, ablation of cvPVHVgat neurons resulted in increased Cort release at the onset of the active phase, affirming the pivotal role of the DMHVgat → cvPVHVgat → PVHCRH pathway in Cort secretion. In summary, our study delineates two parallel pathways transmitting temporal information to PVHCRH neurons, collectively orchestrating the daily surge in Cort in anticipation of the active phase. These findings are crucial to understand the neural circuits regulating Cort secretion, shedding light on the mechanisms governing this physiological process and the coordinated interplay between SCN, DMH, and PVH.
Collapse
Affiliation(s)
- Oscar D. Ramirez-Plascencia
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Roberto De Luca
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Natalia L. S. Machado
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Dominique Eghlidi
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Mudasir A. Khanday
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Sathyajit S. Bandaru
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Francesca Raffin
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
- Department of Biology and Biotechnology “Lazzaro Spallanzani”, University of Pavia, Pavia, PV 27100, Italy
| | - Nina Vujovic
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
- Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Elda Arrigoni
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Clifford B. Saper
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA 02215, USA
| |
Collapse
|
2
|
Mirabella PN, Fenselau H. Advanced neurobiological tools to interrogate metabolism. Nat Rev Endocrinol 2023; 19:639-654. [PMID: 37674015 DOI: 10.1038/s41574-023-00885-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/24/2023] [Indexed: 09/08/2023]
Abstract
Engineered neurobiological tools for the manipulation of cellular activity, such as chemogenetics and optogenetics, have become a cornerstone of modern neuroscience research. These tools are invaluable for the interrogation of the central control of metabolism as they provide a direct means to establish a causal relationship between brain activity and biological processes at the cellular, tissue and organismal levels. The utility of these methods has grown substantially due to advances in cellular-targeting strategies, alongside improvements in the resolution and potency of such tools. Furthermore, the potential to recapitulate endogenous cellular signalling has been enriched by insights into the molecular signatures and activity dynamics of discrete brain cell types. However, each modulatory tool has a specific set of advantages and limitations; therefore, tool selection and suitability are of paramount importance to optimally interrogate the cellular and circuit-based underpinnings of metabolic outcomes within the organism. Here, we describe the key principles and uses of engineered neurobiological tools. We also highlight inspiring applications and outline critical considerations to be made when using these tools within the field of metabolism research. We contend that the appropriate application of these biotechnological advances will enable the delineation of the central circuitry regulating systemic metabolism with unprecedented potential.
Collapse
Affiliation(s)
- Paul Nicholas Mirabella
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Cologne, Germany
- Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany
| | - Henning Fenselau
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Cologne, Germany.
- Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Cologne, Germany.
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, Cologne, Germany.
| |
Collapse
|
3
|
Grzelka K, Wilhelms H, Dodt S, Dreisow ML, Madara JC, Walker SJ, Wu C, Wang D, Lowell BB, Fenselau H. A synaptic amplifier of hunger for regaining body weight in the hypothalamus. Cell Metab 2023; 35:770-785.e5. [PMID: 36965483 PMCID: PMC10160008 DOI: 10.1016/j.cmet.2023.03.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 12/15/2022] [Accepted: 03/01/2023] [Indexed: 03/27/2023]
Abstract
Restricting caloric intake effectively reduces body weight, but most dieters fail long-term adherence to caloric deficit and eventually regain lost weight. Hypothalamic circuits that control hunger drive critically determine body weight; yet, how weight loss sculpts these circuits to motivate food consumption until lost weight is regained remains unclear. Here, we probe the contribution of synaptic plasticity in discrete excitatory afferents on hunger-promoting AgRP neurons. We reveal a crucial role for activity-dependent, remarkably long-lasting amplification of synaptic activity originating from paraventricular hypothalamus thyrotropin-releasing (PVHTRH) neurons in long-term body weight control. Silencing PVHTRH neurons inhibits the potentiation of excitatory input to AgRP neurons and diminishes concomitant regain of lost weight. Brief stimulation of the pathway is sufficient to enduringly potentiate this glutamatergic hunger synapse and triggers an NMDAR-dependent gaining of body weight that enduringly persists. Identification of this activity-dependent synaptic amplifier provides a previously unrecognized target to combat regain of lost weight.
Collapse
Affiliation(s)
- Katarzyna Grzelka
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany
| | - Hannah Wilhelms
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany
| | - Stephan Dodt
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Department of Neuronal Control of Metabolism, Max Planck Institute for Metabolism Research, Cologne, Germany
| | - Marie-Luise Dreisow
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany
| | - Joseph C Madara
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Samuel J Walker
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Chen Wu
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Daqing Wang
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Bradford B Lowell
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA; Program in Neuroscience, Harvard Medical School, Boston, MA 02215, USA.
| | - Henning Fenselau
- Synaptic Transmission in Energy Homeostasis Group, Max Planck Institute for Metabolism Research, Gleueler Strasse 50, 50931 Cologne, Germany; Center for Endocrinology, Diabetes and Preventive Medicine (CEDP), University Hospital Cologne, Kerpener Strasse 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD), University of Cologne, Joseph-Stelzmann-Straße 26, Cologne 50931, Germany.
| |
Collapse
|
4
|
Chen W, Mehlkop O, Scharn A, Nolte H, Klemm P, Henschke S, Steuernagel L, Sotelo-Hitschfeld T, Kaya E, Wunderlich CM, Langer T, Kononenko NL, Giavalisco P, Brüning JC. Nutrient-sensing AgRP neurons relay control of liver autophagy during energy deprivation. Cell Metab 2023; 35:786-806.e13. [PMID: 37075752 PMCID: PMC10173804 DOI: 10.1016/j.cmet.2023.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/01/2023] [Accepted: 03/27/2023] [Indexed: 04/21/2023]
Abstract
Autophagy represents a key regulator of aging and metabolism in sensing energy deprivation. We find that fasting in mice activates autophagy in the liver paralleled by activation of hypothalamic AgRP neurons. Optogenetic and chemogenetic activation of AgRP neurons induces autophagy, alters phosphorylation of autophagy regulators, and promotes ketogenesis. AgRP neuron-dependent induction of liver autophagy relies on NPY release in the paraventricular nucleus of the hypothalamus (PVH) via presynaptic inhibition of NPY1R-expressing neurons to activate PVHCRH neurons. Conversely, inhibiting AgRP neurons during energy deprivation abrogates induction of hepatic autophagy and rewiring of metabolism. AgRP neuron activation increases circulating corticosterone concentrations, and reduction of hepatic glucocorticoid receptor expression attenuates AgRP neuron-dependent activation of hepatic autophagy. Collectively, our study reveals a fundamental regulatory principle of liver autophagy in control of metabolic adaptation during nutrient deprivation.
Collapse
Affiliation(s)
- Weiyi Chen
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Oliver Mehlkop
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Alexandra Scharn
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Hendrik Nolte
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9B, 50931 Cologne, Germany
| | - Paul Klemm
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Sinika Henschke
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Lukas Steuernagel
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Tamara Sotelo-Hitschfeld
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Ecem Kaya
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Claudia Maria Wunderlich
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany
| | - Thomas Langer
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9B, 50931 Cologne, Germany
| | - Natalia L Kononenko
- Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; Center for Physiology and Pathophysiology, Faculty of Medicine and University Hospital Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany
| | - Patrick Giavalisco
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9B, 50931 Cologne, Germany
| | - Jens Claus Brüning
- Max Planck Institute for Metabolism Research, Department of Neuronal Control of Metabolism, Gleueler Str. 50, 50931 Cologne, Germany; Policlinic for Endocrinology, Diabetes, and Preventive Medicine (PEDP), University Hospital Cologne, Kerpener Str. 26, 50924 Cologne, Germany; Excellence Cluster on Cellular Stress Responses in Aging Associated Diseases (CECAD) and Center of Molecular Medicine Cologne (CMMC), University of Cologne, Joseph-Stelzmann-Str. 26, 50931 Cologne, Germany; National Center for Diabetes Research (DZD), Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
| |
Collapse
|
5
|
Zhao R, Grunke SD, Wood CA, Perez GA, Comstock M, Li MH, Singh AK, Park KW, Jankowsky JL. Activity disruption causes degeneration of entorhinal neurons in a mouse model of Alzheimer's circuit dysfunction. eLife 2022; 11:e83813. [PMID: 36468693 PMCID: PMC9873254 DOI: 10.7554/elife.83813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative diseases are characterized by selective vulnerability of distinct cell populations; however, the cause for this specificity remains elusive. Here, we show that entorhinal cortex layer 2 (EC2) neurons are unusually vulnerable to prolonged neuronal inactivity compared with neighboring regions of the temporal lobe, and that reelin + stellate cells connecting EC with the hippocampus are preferentially susceptible within the EC2 population. We demonstrate that neuronal death after silencing can be elicited through multiple independent means of activity inhibition, and that preventing synaptic release, either alone or in combination with electrical shunting, is sufficient to elicit silencing-induced degeneration. Finally, we discovered that degeneration following synaptic silencing is governed by competition between active and inactive cells, which is a circuit refinement process traditionally thought to end early in postnatal life. Our data suggests that the developmental window for wholesale circuit plasticity may extend into adulthood for specific brain regions. We speculate that this sustained potential for remodeling by entorhinal neurons may support lifelong memory but renders them vulnerable to prolonged activity changes in disease.
Collapse
Affiliation(s)
- Rong Zhao
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Stacy D Grunke
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Caleb A Wood
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Gabriella A Perez
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Melissa Comstock
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Ming-Hua Li
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Anand K Singh
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Kyung-Won Park
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Joanna L Jankowsky
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
- Departments of Neurology, Neurosurgery, and Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| |
Collapse
|
6
|
Koniuszewski F, Vogel FD, Bampali K, Fabjan J, Seidel T, Scholze P, Schmiedhofer PB, Langer T, Ernst M. Molecular Mingling: Multimodal Predictions of Ligand Promiscuity in Pentameric Ligand-Gated Ion Channels. Front Mol Biosci 2022; 9:860246. [PMID: 35615739 PMCID: PMC9124788 DOI: 10.3389/fmolb.2022.860246] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 03/28/2022] [Indexed: 01/23/2023] Open
Abstract
Background: Human pentameric ligand-gated ion channels (pLGICs) comprise nicotinic acetylcholine receptors (nAChRs), 5-hydroxytryptamine type 3 receptors (5-HT3Rs), zinc-activated channels (ZAC), γ-aminobutyric acid type A receptors (GABAARs) and glycine receptors (GlyRs). They are recognized therapeutic targets of some of the most prescribed drugs like general anesthetics, anxiolytics, smoking cessation aids, antiemetics and many more. Currently, approximately 100 experimental structures of pLGICs with ligands bound exist in the protein data bank (PDB). These atomic-level 3D structures enable the generation of a comprehensive binding site inventory for the superfamily and the in silico prediction of binding site properties. Methods: A panel of high throughput in silico methods including pharmacophore screening, conformation analysis and descriptor calculation was applied to a selection of allosteric binding sites for which in vitro screens are lacking. Variant abundance near binding site forming regions and computational docking complement the approach. Results: The structural data reflects known and novel binding sites, some of which may be unique to individual receptors, while others are broadly conserved. The membrane spanning domain, comprising four highly conserved segments, contains ligand interaction sites for which in vitro assays suitable for high throughput screenings are critically lacking. This is also the case for structurally more variable novel sites in the extracellular domain. Our computational results suggest that the phytocannabinoid Δ9-tetrahydrocannabinol (Δ9-THC) can utilize multiple pockets which are likely to exist on most superfamily members. Conclusion: With this study, we explore the potential for polypharmacology among pLGICs. Our data suggest that ligands can display two forms of promiscuity to an extent greater than what has been realized: 1) Ligands can interact with homologous sites in many members of the superfamily, which bears toxicological relevance. 2) Multiple pockets in distinct localizations of individual receptor subtypes share common ligands, which counteracts efforts to develop selective agents. Moreover, conformational states need to be considered for in silico drug screening, as certain binding sites display considerable flexibility. In total, this work contributes to a better understanding of polypharmacology across pLGICs and provides a basis for improved structure guided in silico drug development and drug derisking.
Collapse
Affiliation(s)
- Filip Koniuszewski
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Florian D. Vogel
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Konstantina Bampali
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Jure Fabjan
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Thomas Seidel
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Petra Scholze
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Philip B. Schmiedhofer
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| | - Thierry Langer
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Margot Ernst
- Department of Pathobiology of the Nervous System, Center for Brain Research, Medical University Vienna, Vienna, Austria
| |
Collapse
|
7
|
Lovinger DM, Mateo Y, Johnson KA, Engi SA, Antonazzo M, Cheer JF. Local modulation by presynaptic receptors controls neuronal communication and behaviour. Nat Rev Neurosci 2022; 23:191-203. [PMID: 35228740 PMCID: PMC10709822 DOI: 10.1038/s41583-022-00561-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2022] [Indexed: 12/15/2022]
Abstract
Central nervous system neurons communicate via fast synaptic transmission mediated by ligand-gated ion channel (LGIC) receptors and slower neuromodulation mediated by G protein-coupled receptors (GPCRs). These receptors influence many neuronal functions, including presynaptic neurotransmitter release. Presynaptic LGIC and GPCR activation by locally released neurotransmitters influences neuronal communication in ways that modify effects of somatic action potentials. Although much is known about presynaptic receptors and their mechanisms of action, less is known about when and where these receptor actions alter release, especially in vivo. This Review focuses on emerging evidence for important local presynaptic receptor actions and ideas for future studies in this area.
Collapse
Affiliation(s)
- David M Lovinger
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA.
| | - Yolanda Mateo
- Laboratory for Integrative Neuroscience, National Institute on Alcohol Abuse and Alcoholism, Bethesda, MD, USA
| | - Kari A Johnson
- Department of Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Sheila A Engi
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Mario Antonazzo
- Department of Anatomy and Neurobiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joseph F Cheer
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
8
|
Miura Y, Senoo A, Doura T, Kiyonaka S. Chemogenetics of cell surface receptors: beyond genetic and pharmacological approaches. RSC Chem Biol 2022; 3:269-287. [PMID: 35359495 PMCID: PMC8905536 DOI: 10.1039/d1cb00195g] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 01/20/2022] [Indexed: 11/29/2022] Open
Abstract
Cell surface receptors transmit extracellular information into cells. Spatiotemporal regulation of receptor signaling is crucial for cellular functions, and dysregulation of signaling causes various diseases. Thus, it is highly desired to control receptor functions with high spatial and/or temporal resolution. Conventionally, genetic engineering or chemical ligands have been used to control receptor functions in cells. As the alternative, chemogenetics has been proposed, in which target proteins are genetically engineered to interact with a designed chemical partner with high selectivity. The engineered receptor dissects the function of one receptor member among a highly homologous receptor family in a cell-specific manner. Notably, some chemogenetic strategies have been used to reveal the receptor signaling of target cells in living animals. In this review, we summarize the developing chemogenetic methods of transmembrane receptors for cell-specific regulation of receptor signaling. We also discuss the prospects of chemogenetics for clinical applications.
Collapse
Affiliation(s)
- Yuta Miura
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University Nagoya 464-8603 Japan
| | - Akinobu Senoo
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University Nagoya 464-8603 Japan
| | - Tomohiro Doura
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University Nagoya 464-8603 Japan
| | - Shigeki Kiyonaka
- Department of Biomolecular Engineering, Graduate School of Engineering, Nagoya University Nagoya 464-8603 Japan
| |
Collapse
|
9
|
Chemogenetics as a neuromodulatory approach to treating neuropsychiatric diseases and disorders. Mol Ther 2022; 30:990-1005. [PMID: 34861415 PMCID: PMC8899595 DOI: 10.1016/j.ymthe.2021.11.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 11/12/2021] [Accepted: 11/29/2021] [Indexed: 01/01/2023] Open
Abstract
Chemogenetics enables precise, non-invasive, and reversible modulation of neural activity via the activation of engineered receptors that are pharmacologically selective to endogenous or exogenous ligands. With recent advances in therapeutic gene delivery, chemogenetics is poised to support novel interventions against neuropsychiatric diseases and disorders. To evaluate its translational potential, we performed a scoping review of applications of chemogenetics that led to the reversal of molecular and behavioral deficits in studies relevant to neuropsychiatric diseases and disorders. In this review, we present these findings and discuss the potential and challenges for using chemogenetics as a precision medicine-based neuromodulation strategy.
Collapse
|
10
|
Poth KM, Texakalidis P, Boulis NM. Chemogenetics: Beyond Lesions and Electrodes. Neurosurgery 2021; 89:185-195. [PMID: 33913505 PMCID: PMC8279839 DOI: 10.1093/neuros/nyab147] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 02/26/2021] [Indexed: 01/14/2023] Open
Abstract
The field of chemogenetics has rapidly expanded over the last decade, and engineered receptors are currently utilized in the lab to better understand molecular interactions in the nervous system. We propose that chemogenetic receptors can be used for far more than investigational purposes. The potential benefit of adding chemogenetic neuromodulation to the current neurosurgical toolkit is substantial. There are several conditions currently treated surgically, electrically, and pharmacologically in clinic, and this review highlights how chemogenetic neuromodulation could improve patient outcomes over current neurosurgical techniques. We aim to emphasize the need to take these techniques from bench to bedside.
Collapse
Affiliation(s)
- Kelly M Poth
- Department of Neurosurgery, Emory University, Atlanta, Georgia, USA
| | | | | |
Collapse
|
11
|
Xu Q, Wang DR, Dong H, Chen L, Lu J, Lazarus M, Cherasse Y, Chen GH, Qu WM, Huang ZL. Medial Parabrachial Nucleus Is Essential in Controlling Wakefulness in Rats. Front Neurosci 2021; 15:645877. [PMID: 33841086 PMCID: PMC8027131 DOI: 10.3389/fnins.2021.645877] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/09/2021] [Indexed: 12/03/2022] Open
Abstract
Activation of the parabrachial nucleus (PB) in the brainstem induced wakefulness in rats, suggesting which is an important nucleus that controls arousal. However, the sub-regions of PB in regulating sleep-wake cycle is still unclear. Here, we employ chemogenetics and optogenetics strategies and find that activation of the medial part of PB (MPB), but not the lateral part, induces continuous wakefulness for 10 h without sleep rebound in neither sleep amount nor the power spectra. Optogenetic activation of glutamatergic MPB neurons in sleeping rats immediately wake rats mediated by the basal forebrain (BF) and lateral hypothalamus (LH), but not the ventral medial thalamus. Most importantly, chemogenetic inhibition of PB neurons decreases wakefulness for 10 h. Conclusively, these findings indicate that the glutamatergic MPB neurons are essential in controlling wakefulness, and that MPB-BF and MPB-LH pathways are the major neuronal circuits.
Collapse
Affiliation(s)
- Qi Xu
- Department of Physiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Dian-Ru Wang
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Hui Dong
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Li Chen
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Jun Lu
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Michael Lazarus
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Yoan Cherasse
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba, Japan
| | - Gui-Hai Chen
- Department of Sleep Disorders and Neurology, The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Wei-Min Qu
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| | - Zhi-Li Huang
- Department of Pharmacology, School of Basic Medical Sciences, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology, MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
| |
Collapse
|
12
|
Xue W, Snoeck S, Njiru C, Inak E, Dermauw W, Van Leeuwen T. Geographical distribution and molecular insights into abamectin and milbemectin cross-resistance in European field populations of Tetranychus urticae. PEST MANAGEMENT SCIENCE 2020; 76:2569-2581. [PMID: 32237053 DOI: 10.1002/ps.5831] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/23/2020] [Accepted: 04/01/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Milbemectin and abamectin are frequently used to control the spider mite Tetranychus urticae. The development of abamectin resistance in this major pest has become an increasing problem worldwide, potentially compromising the use of milbemectin. In this study, a large collection of European field populations was screened for milbemectin and abamectin resistance, and both target-site and metabolic (cross-)resistance mechanisms were investigated. RESULTS High to very high levels of abamectin resistance were found in one third of all populations, while milbemectin resistance levels were low for most populations. The occurrence of well-known target-site resistance mutations in glutamate-gated chloride channels (G314D in GluCl1 and G326E in GluCl3) was documented in the most resistant populations. However, a new mutation, I321T in GluCl3, was also uncovered in three resistant populations, while a V327G and L329F mutation was found in GluCl3 of one resistant population. A differential gene-expression analysis revealed the overexpression of detoxification genes, more specifically cytochrome P450 monooxygenase (P450) and UDP-glycosyltransferase (UGT) genes. Multiple UGTs were functionally expressed, and their capability to glycosylate abamectin and milbemectin, was tested and confirmed. CONCLUSIONS We found a clear correlation between abamectin and milbemectin resistance in European T. urticae populations, but as milbemectin resistance levels were low, the observed cross-resistance is probably not of operational importance. The presence of target-site resistance mutations in GluCl genes was confirmed in most but not all resistant populations. Gene-expression analysis and functional characterization of P450s and UGTs suggests that also metabolic abamectin resistance mechanisms are common in European T. urticae populations. © 2020 Society of Chemical Industry.
Collapse
Affiliation(s)
- Wenxin Xue
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| | - Simon Snoeck
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| | - Christine Njiru
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| | - Emre Inak
- Department of Plant Protection, Faculty of Agriculture, Ankara University, Diskapi, Ankara, Turkey
| | - Wannes Dermauw
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| | - Thomas Van Leeuwen
- Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| |
Collapse
|
13
|
Chemogenetics a robust approach to pharmacology and gene therapy. Biochem Pharmacol 2020; 175:113889. [DOI: 10.1016/j.bcp.2020.113889] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/26/2020] [Indexed: 12/20/2022]
|
14
|
Venner A, Todd WD, Fraigne J, Bowrey H, Eban-Rothschild A, Kaur S, Anaclet C. Newly identified sleep-wake and circadian circuits as potential therapeutic targets. Sleep 2020; 42:5306564. [PMID: 30722061 DOI: 10.1093/sleep/zsz023] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 01/25/2019] [Indexed: 02/06/2023] Open
Abstract
Optogenetics and chemogenetics are powerful tools, allowing the specific activation or inhibition of targeted neuronal subpopulations. Application of these techniques to sleep and circadian research has resulted in the unveiling of several neuronal populations that are involved in sleep-wake control, and allowed a comprehensive interrogation of the circuitry through which these nodes are coordinated to orchestrate the sleep-wake cycle. In this review, we discuss six recently described sleep-wake and circadian circuits that show promise as therapeutic targets for sleep medicine. The parafacial zone (PZ) and the ventral tegmental area (VTA) are potential druggable targets for the treatment of insomnia. The brainstem circuit underlying rapid eye movement sleep behavior disorder (RBD) offers new possibilities for treating RBD and neurodegenerative synucleinopathies, whereas the parabrachial nucleus, as a nexus linking arousal state control and breathing, is a promising target for developing treatments for sleep apnea. Therapies that act upon the hypothalamic circuitry underlying the circadian regulation of aggression or the photic regulation of arousal and mood pathway carry enormous potential for helping to reduce the socioeconomic burden of neuropsychiatric and neurodegenerative disorders on society. Intriguingly, the development of chemogenetics as a therapeutic strategy is now well underway and such an approach has the capacity to lead to more focused and less invasive therapies for treating sleep-wake disorders and related comorbidities.
Collapse
Affiliation(s)
- Anne Venner
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA.,Department of Neurology, Harvard Medical School, Boston, MA
| | - William D Todd
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA.,Department of Neurology, Harvard Medical School, Boston, MA
| | - Jimmy Fraigne
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Hannah Bowrey
- Department of Psychiatry, Rutgers Biomedical Health Sciences, Rutgers University, Newark, NJ.,Save Sight Institute, The University of Sydney, Sydney, New South Wales, Australia
| | | | - Satvinder Kaur
- Department of Neurology, Beth Israel Deaconess Medical Center, Boston, MA.,Department of Neurology, Harvard Medical School, Boston, MA
| | - Christelle Anaclet
- Department of Neurobiology, Brudnick Neuropsychiatric Research Institute, NeuroNexus Institute, Graduate Program in Neuroscience - Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA
| |
Collapse
|
15
|
Qi W, Clark JM, Suvorov A, Park Y. Ivermectin decreases triglyceride accumulation by inhibiting adipogenesis of 3T3-L1 preadipocytes. Food Chem Toxicol 2019; 131:110576. [DOI: 10.1016/j.fct.2019.110576] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 06/07/2019] [Accepted: 06/10/2019] [Indexed: 12/18/2022]
|
16
|
Lieb A, Weston M, Kullmann DM. Designer receptor technology for the treatment of epilepsy. EBioMedicine 2019; 43:641-649. [PMID: 31078519 PMCID: PMC6558262 DOI: 10.1016/j.ebiom.2019.04.059] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 04/26/2019] [Accepted: 04/29/2019] [Indexed: 12/20/2022] Open
Abstract
Epilepsy remains refractory to medical treatment in ~30% of patients despite decades of new drug development. Neurosurgery to remove or disconnect the seizure focus is often curative but frequently contraindicated by risks of irreversible impairment to brain function. Novel therapies are therefore required that better balance seizure suppression against the risks of side effects. Among experimental gene therapies, chemogenetics has the major advantage that the action on the epileptogenic zone can be modulated on demand. Two broad approaches are to use a designer G-protein-coupled receptor or a modified ligand gated ion channel, targeted to specific neurons in the epileptogenic zone using viral vectors and cell-type selective promoters. The receptor can be activated on demand by either an exogenous compound or by pathological levels of extracellular glutamate that occur in epileptogenic tissue. We review the principal designer receptor technologies and their modes of action. We compare the drawbacks and benefits of each designer receptor with particular focus on the drug activators and the potential for clinical translation in epilepsy. Inhibitory designer receptors (DRs) allow on-demand suppression of seizures upon activation by exogenous drugs or endogenous neurotransmitters. DRs include modified G-protein coupled receptors, chimaeric ligand-gated ion channels, and mutated non-mammalian channels. Identification of drug activators of DRs that are already approved for use in humans significantly accelerates clinical translation.
Collapse
Affiliation(s)
- Andreas Lieb
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, UK
| | - Mikail Weston
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, UK
| | - Dimitri M Kullmann
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, University College London, UK.
| |
Collapse
|
17
|
Nguyen HX, Bursac N. Ion channel engineering for modulation and de novo generation of electrical excitability. Curr Opin Biotechnol 2019; 58:100-107. [PMID: 30776744 DOI: 10.1016/j.copbio.2019.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 01/02/2019] [Indexed: 02/07/2023]
Abstract
Ion channels play essential roles in regulating electrical properties of excitable tissues. By leveraging various ion channel gating mechanisms, scientists have developed a versatile set of genetically encoded tools to modulate intrinsic tissue excitability under different experimental settings. In this article, we will review how ion channels activated by voltage, light, small chemicals, stretch, and temperature have been customized to enable control of tissue excitability both in vitro and in vivo. Advantages and limitations of each of these ion channel-engineering platforms will be discussed and notable applications will be highlighted. Furthermore, we will describe recent progress on de novo generation of excitable tissues via expression of appropriate sets of engineered voltage-gated ion channels and discuss potential therapeutic implications.
Collapse
Affiliation(s)
- Hung X Nguyen
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA
| | - Nenad Bursac
- Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
| |
Collapse
|
18
|
Aldrin-Kirk P, Björklund T. Practical Considerations for the Use of DREADD and Other Chemogenetic Receptors to Regulate Neuronal Activity in the Mammalian Brain. Methods Mol Biol 2019; 1937:59-87. [PMID: 30706390 DOI: 10.1007/978-1-4939-9065-8_4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Chemogenetics is the process of genetically expressing a macromolecule receptor capable of modulating the activity of the cell in response to selective chemical ligand. This chapter will cover the chemogenetic technologies that are available to date, focusing on the commonly available engineered or otherwise modified ligand-gated ion channels and G-protein-coupled receptors in the context of neuromodulation. First, we will give a brief overview of each chemogenetic approach as well as in vitro/in vivo applications, then we will list their strengths and weaknesses. Finally, we will provide tips for ligand application in each case.Each technology has specific limitations that make them more or less suitable for different applications in neuroscience although we will focus mainly on the most commonly used and versatile family named designer receptors exclusively activated by designer drugs or DREADDs. We here describe the most common cases where these can be implemented and provide tips on how and where these technologies can be applied in the field of neuroscience.
Collapse
Affiliation(s)
- Patrick Aldrin-Kirk
- Molecular Neuromodulation, Wallenberg Neuroscience Center, Lund University, Lund, Sweden
| | - Tomas Björklund
- Molecular Neuromodulation, Wallenberg Neuroscience Center, Lund University, Lund, Sweden.
| |
Collapse
|
19
|
Schoderboeck L, Wicky HE, Abraham WC, Hughes SM. Genetic Targeting and Chemogenetic Inhibition of Newborn Neurons. Hum Gene Ther Methods 2018; 29:259-268. [PMID: 30526082 DOI: 10.1089/hgtb.2018.182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to develop a method to silence a very specific set of cells in a spatially and temporally refined manner. Here, an approach is presented that combines the use of a transgenic mouse line, expressing cre recombinase under a nestin promoter, with lentiviral delivery of a floxed, ivermectin (IVM)-gated chloride channel construct to the dentate gyrus. This approach was used to express an IVM-sensitive chloride channel in newly born granule cells in adult mouse brains, and its ability to silence neuronal activity was tested by analyzing the effect on immediate early gene expression in vitro in cre-transgenic primary neuronal cultures. IVM treatment of cells expressing the chloride channel prevented gabazine-induced expression of the immediate early gene product EGR1, while cells expressing a control inactive channel or no channel retained their EGR1 response. Thus, a genetic strategy is presented for targeting a specific neurogenic niche for transgene expression in the adult mouse brain, and proof of principle is shown that it can be used in vitro as a method for silencing neuronal activity.
Collapse
Affiliation(s)
- Lucia Schoderboeck
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,Department of Psychology, University of Otago, Dunedin, New Zealand.,Brain Health Research Centre and Brain Research New Zealand, and University of Otago, Dunedin, New Zealand.,Genetics Otago, University of Otago, Dunedin, New Zealand
| | - Hollie E Wicky
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,Brain Health Research Centre and Brain Research New Zealand, and University of Otago, Dunedin, New Zealand.,Genetics Otago, University of Otago, Dunedin, New Zealand
| | - Wickliffe C Abraham
- Department of Psychology, University of Otago, Dunedin, New Zealand.,Brain Health Research Centre and Brain Research New Zealand, and University of Otago, Dunedin, New Zealand
| | - Stephanie M Hughes
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,Brain Health Research Centre and Brain Research New Zealand, and University of Otago, Dunedin, New Zealand.,Genetics Otago, University of Otago, Dunedin, New Zealand
| |
Collapse
|
20
|
Abstract
Chemogenetic technologies enable selective pharmacological control of specific cell populations. An increasing number of approaches have been developed that modulate different signaling pathways. Selective pharmacological control over G protein-coupled receptor signaling, ion channel conductances, protein association, protein stability, and small molecule targeting allows modulation of cellular processes in distinct cell types. Here, we review these chemogenetic technologies and instances of their applications in complex tissues in vivo and ex vivo.
Collapse
Affiliation(s)
- Deniz Atasoy
- Department of Physiology, School of Medicine and Regenerative-Restorative Medicine Research Center (REMER), Istanbul Medipol University , Istanbul , Turkey ; and Janelia Research Campus, Howard Hughes Medical Institute , Ashburn, Virginia
| | - Scott M Sternson
- Department of Physiology, School of Medicine and Regenerative-Restorative Medicine Research Center (REMER), Istanbul Medipol University , Istanbul , Turkey ; and Janelia Research Campus, Howard Hughes Medical Institute , Ashburn, Virginia
| |
Collapse
|
21
|
Machado NLS, Abbott SBG, Resch JM, Zhu L, Arrigoni E, Lowell BB, Fuller PM, Fontes MAP, Saper CB. A Glutamatergic Hypothalamomedullary Circuit Mediates Thermogenesis, but Not Heat Conservation, during Stress-Induced Hyperthermia. Curr Biol 2018; 28:2291-2301.e5. [PMID: 30017482 DOI: 10.1016/j.cub.2018.05.064] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 05/11/2018] [Accepted: 05/22/2018] [Indexed: 11/30/2022]
Abstract
Stress elicits a variety of autonomic responses, including hyperthermia (stress fever) in humans and animals. In this present study, we investigated the circuit basis for thermogenesis and heat conservation during this response. We first demonstrated the glutamatergic identity of the dorsal hypothalamic area (DHAVglut2) neurons that innervate the raphe pallidus nucleus (RPa) to regulate core temperature (Tc) and mediate stress-induced hyperthermia. Then, using chemogenetic and optogenetic methods to manipulate this hypothalamomedullary circuit, we found that activation of DHAVglut2 neurons potently drove an increase in Tc, but surprisingly, stress-induced hyperthermia was only reduced by about one-third when they were inhibited. Further investigation showed that DHAVglut2 neurons activate brown adipose tissue (BAT) but do not cause vasoconstriction, instead allowing reflex tail artery vasodilation as a response to BAT-induced hyperthermia. Retrograde rabies virus tracing revealed projections from DHAVglut2 neurons to RPaVglut3, but not to RPaGABA neurons, and identified a set of inputs to DHAVglut2 → RPa neurons that are likely to mediate BAT activation. The dissociation of the DHAVglut2 thermogenic pathway from the thermoregulatory vasoconstriction (heat-conserving) pathway may explain stress flushing (skin vasodilation but a feeling of being too hot) during stressful times.
Collapse
Affiliation(s)
- Natalia L S Machado
- Department of Neurology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA; Department of Physiology and Biophysics, Federal University of Minas Gerais, Antonio Carlos Avenue, Belo Horizonte 31270-901, Brazil
| | - Stephen B G Abbott
- Department of Neurology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA; Department of Pharmacology, University of Virginia, Jefferson Park Avenue, Charlottesville, VA 22908, USA
| | - Jon M Resch
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA
| | - Lin Zhu
- Department of Neurology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA
| | - Elda Arrigoni
- Department of Neurology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA
| | - Bradford B Lowell
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA
| | - Patrick M Fuller
- Department of Neurology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA
| | - Marco A P Fontes
- Department of Physiology and Biophysics, Federal University of Minas Gerais, Antonio Carlos Avenue, Belo Horizonte 31270-901, Brazil
| | - Clifford B Saper
- Department of Neurology, Beth Israel-Deaconess Medical Center, Harvard Medical School, Blackfan Circle, Boston, MA 02215, USA.
| |
Collapse
|
22
|
A hypothalamic circuit for the circadian control of aggression. Nat Neurosci 2018; 21:717-724. [PMID: 29632359 PMCID: PMC5920747 DOI: 10.1038/s41593-018-0126-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 02/09/2018] [Indexed: 11/21/2022]
Abstract
“Sundowning” in dementia and Alzheimer’s disease is characterized by early evening agitation and aggression. While such periodicity suggests a circadian origin, whether the circadian clock directly regulates aggressive behavior is unknown. We demonstrate that a daily rhythm in aggression propensity in male mice is gated by GABAergic subparaventricular zone (SPZGABA) neurons, the major postsynaptic targets of the central circadian clock, the suprachiasmatic nucleus (SCN). Optogenetic mapping revealed that SPZGABA neurons receive input from vasoactive intestinal polypeptide SCN neurons and innervate neurons in the ventrolateral part of the ventromedial hypothalamus (VMHvl) known to regulate aggression. Additionally, VMH-projecting dorsal SPZ neurons are more active during early day than early night, and acute chemogenetic inhibition of SPZGABA transmission phase-dependently increases aggression. Finally, SPZGABA-recipient central VMH neurons directly innervate VMHvl neurons and activation of this intra-VMH circuit drove attack behavior. Altogether, we reveal a functional polysynaptic circuit by which the SCN clock regulates aggression.
Collapse
|
23
|
Campbell EJ, Marchant NJ. The use of chemogenetics in behavioural neuroscience: receptor variants, targeting approaches and caveats. Br J Pharmacol 2018; 175:994-1003. [PMID: 29338070 DOI: 10.1111/bph.14146] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 12/13/2017] [Accepted: 12/27/2017] [Indexed: 12/18/2022] Open
Abstract
The last decade has seen major advances in neuroscience tools allowing us to selectively modulate cellular pathways in freely moving animals. Chemogenetic approaches such as designer receptors exclusively activated by designer drugs (DREADDs) permit the remote control of neuronal function by systemic drug administration. These approaches have dramatically advanced our understanding of the neural control of behaviour. Here, we review the different techniques and genetic approaches available for the restriction of chemogenetic receptors to defined neuronal populations. We highlight the use of a dual virus approach to target specific circuitries and the effectiveness of different routes of administration of designer drugs. Finally, we discuss the potential caveats associated with DREADDs including off-target effects of designer drugs, the effects of chronic chemogenetic receptor activation and the issue of collateral projections associated with DREADD activation and inhibition.
Collapse
Affiliation(s)
- Erin J Campbell
- The Florey Institute of Neuroscience and Mental Health, Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
| | - Nathan J Marchant
- The Florey Institute of Neuroscience and Mental Health, Florey Department of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia.,Department of Anatomy & Neurosciences, VU University Medical Center, Amsterdam, The Netherlands
| |
Collapse
|
24
|
Hippocampus-driven feed-forward inhibition of the prefrontal cortex mediates relapse of extinguished fear. Nat Neurosci 2018; 21:384-392. [PMID: 29403033 DOI: 10.1038/s41593-018-0073-9] [Citation(s) in RCA: 144] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/19/2017] [Indexed: 12/18/2022]
Abstract
The medial prefrontal cortex (mPFC) has been implicated in the extinction of emotional memories, including conditioned fear. We found that ventral hippocampal (vHPC) projections to the infralimbic (IL) cortex recruited parvalbumin-expressing interneurons to counter the expression of extinguished fear and promote fear relapse. Whole-cell recordings ex vivo revealed that optogenetic activation of vHPC input to amygdala-projecting pyramidal neurons in the IL was dominated by feed-forward inhibition. Selectively silencing parvalbumin-expressing, but not somatostatin-expressing, interneurons in the IL eliminated vHPC-mediated inhibition. In behaving rats, pharmacogenetic activation of vHPC→IL projections impaired extinction recall, whereas silencing IL projectors diminished fear renewal. Intra-IL infusion of GABA receptor agonists or antagonists, respectively, reproduced these effects. Together, our findings describe a previously unknown circuit mechanism for the contextual control of fear, and indicate that vHPC-mediated inhibition of IL is an essential neural substrate for fear relapse.
Collapse
|
25
|
Spampanato J, Gibson A, Dudek FE. The antihelminthic moxidectin enhances tonic GABA currents in rodent hippocampal pyramidal neurons. J Neurophysiol 2018; 119:1693-1698. [PMID: 29364072 DOI: 10.1152/jn.00587.2017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Macrocyclic lactones (MLs) are commonly used treatments for parasitic worm and insect infections in humans, livestock, and companion animals. MLs target the invertebrate glutamate-activated chloride channel that is not present in vertebrates. MLs are not entirely inert in vertebrates, though; they have been reported to have activity in heterologous expression systems consisting of ligand-gated ion channels that are present in the mammalian central nervous system (CNS). However, these compounds are typically not able to reach significant concentrations in the CNS because of the activity of the blood-brain barrier P-glycoprotein extrusion system. Despite this, these compounds are able to reach low levels in the CNS that may be useful in the design of novel "designer" ligand-receptor systems that can be used to directly investigate neuronal control of behavior in mammals and have potential for use in treating human neurological diseases. To determine whether MLs might affect neurons in intact brains, we investigated the activity of the ML moxidectin (MOX) at native GABA receptors. Specifically, we recorded tonic and phasic miniature inhibitory postsynaptic currents (mIPSCs) in ex vivo brain slices. Our data show that MOX potentiated tonic GABA currents in a dose-dependent manner but had no concomitant effects on phasic GABA currents (i.e., MOX had no effect on the amplitude, frequency, or decay kinetics of mIPSCs). These studies indicate that behavioral experiments that implement a ML-based novel ligand-receptor system should take care to control for potential effects of the ML on native tonic GABA receptors. NEW & NOTEWORTHY We have identified a novel mechanism of action in the mammalian central nervous system for the antihelminthic moxidectin, commonly prescribed to animals worldwide and currently being evaluated for use in humans. Specifically, moxidectin applied to rodent brain slices selectively enhanced the tonic GABA conductance of hippocampal pyramidal neurons.
Collapse
Affiliation(s)
- Jay Spampanato
- Department of Neurosurgery, University of Utah School of Medicine , Salt Lake City, Utah
| | - Anne Gibson
- Department of Neurosurgery, University of Utah School of Medicine , Salt Lake City, Utah
| | - F Edward Dudek
- Department of Neurosurgery, University of Utah School of Medicine , Salt Lake City, Utah
| |
Collapse
|
26
|
Chen IS, Kubo Y. Ivermectin and its target molecules: shared and unique modulation mechanisms of ion channels and receptors by ivermectin. J Physiol 2017; 596:1833-1845. [PMID: 29063617 DOI: 10.1113/jp275236] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/06/2017] [Indexed: 12/11/2022] Open
Abstract
Ivermectin (IVM) is an antiparasitic drug that is used worldwide and rescues hundreds of millions of people from onchocerciasis and lymphatic filariasis. It was discovered by Satoshi Ōmura and William C. Campbell, to whom the 2015 Nobel Prize in Physiology or Medicine was awarded. It kills parasites by activating glutamate-gated Cl- channels, and it also targets several ligand-gated ion channels and receptors, including Cys-loop receptors, P2X4 receptors and fernesoid X receptors. Recently, we found that IVM also activates a novel target, the G-protein-gated inwardly rectifying K+ channel, and also identified the structural determinant for the activation. In this review, we aim to provide an update and summary of recent progress in the identification of IVM targets, as well as their modulation mechanisms, through molecular structures, chimeras and site-directed mutagenesis, and molecular docking and modelling studies.
Collapse
Affiliation(s)
- I-Shan Chen
- Division of Biophysics and Neurobiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, Okazaki, 444-8585, Japan.,Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Hayama, 240-0193, Japan
| | - Yoshihiro Kubo
- Division of Biophysics and Neurobiology, Department of Molecular and Cellular Physiology, National Institute for Physiological Sciences, Okazaki, 444-8585, Japan.,Department of Physiological Sciences, School of Life Science, SOKENDAI (The Graduate University for Advanced Studies), Hayama, 240-0193, Japan
| |
Collapse
|
27
|
Atif M, Estrada-Mondragon A, Nguyen B, Lynch JW, Keramidas A. Effects of glutamate and ivermectin on single glutamate-gated chloride channels of the parasitic nematode H. contortus. PLoS Pathog 2017; 13:e1006663. [PMID: 28968469 PMCID: PMC5638611 DOI: 10.1371/journal.ppat.1006663] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 10/12/2017] [Accepted: 09/22/2017] [Indexed: 12/12/2022] Open
Abstract
Ivermectin (IVM) is a widely-used anthelmintic that works by binding to and activating glutamate-gated chloride channel receptors (GluClRs) in nematodes. The resulting chloride flux inhibits the pharyngeal muscle cells and motor neurons of nematodes, causing death by paralysis or starvation. IVM resistance is an emerging problem in many pest species, necessitating the development of novel drugs. However, drug optimisation requires a quantitative understanding of GluClR activation and modulation mechanisms. Here we investigated the biophysical properties of homomeric α (avr-14b) GluClRs from the parasitic nematode, H. contortus, in the presence of glutamate and IVM. The receptor proved to be highly responsive to low nanomolar concentrations of both compounds. Analysis of single receptor activations demonstrated that the GluClR oscillates between multiple functional states upon the binding of either ligand. The G36’A mutation in the third transmembrane domain, which was previously thought to hinder access of IVM to its binding site, was found to decrease the duration of active periods and increase receptor desensitisation. On an ensemble macropatch level the mutation gave rise to enhanced current decay and desensitisation rates. Because these responses were common to both glutamate and IVM, and were observed under conditions where agonist binding sites were likely saturated, we infer that G36’A affects the intrinsic properties of the receptor with no specific effect on IVM binding mechanisms. These unexpected results provide new insights into the activation and modulatory mechanisms of the H. contortus GluClRs and provide a mechanistic framework upon which the actions of drugs can be reliably interpreted. IVM is a gold standard anti-parasitic drug that is used extensively to control invertebrate parasites pest species. The drug targets the glutamate-gated chloride channel receptor (GluClR) found on neurons and muscle cells of these organisms, causing paralysis and death. However, IVM resistance is becoming a serious problem in human and animal health, as well as human food production. We provide the first comprehensive investigation of the functional properties of the GluClR of H. contortus, which is a major parasite in grazing animals, such as sheep and goats. We compared glutamate and IVM induced activity of the wild-type and a mutant GluClR, G36’A, that markedly reduces IVM sensitivity in wild populations of pests. Our data demonstrate that the mutation reduces IVM sensitivity by altering the functional properties of the GluClR rather than specifically affecting the binding of IVM, even though the mutation occurs at the IVM binding site. This study provides a mechanistic framework upon which the actions of new candidate anthelmintic drugs can be interpreted.
Collapse
Affiliation(s)
- Mohammed Atif
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | | | - Bindi Nguyen
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
| | - Joseph W. Lynch
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
- * E-mail: (AK); (JL)
| | - Angelo Keramidas
- Queensland Brain Institute, The University of Queensland, Brisbane, Australia
- * E-mail: (AK); (JL)
| |
Collapse
|
28
|
Degani-Katzav N, Gortler R, Weissman M, Paas Y. Mutational Analysis at Intersubunit Interfaces of an Anionic Glutamate Receptor Reveals a Key Interaction Important for Channel Gating by Ivermectin. Front Mol Neurosci 2017; 10:92. [PMID: 28428744 PMCID: PMC5382172 DOI: 10.3389/fnmol.2017.00092] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 03/17/2017] [Indexed: 11/13/2022] Open
Abstract
The broad-spectrum anthelmintic drug ivermectin (IVM) activates and stabilizes an open-channel conformation of invertebrate chloride-selective glutamate receptors (GluClRs), thereby causing a continuous inflow of chloride ions and sustained membrane hyperpolarization. These effects suppress nervous impulses and vital physiological processes in parasitic nematodes. The GluClRs are pentamers. Homopentameric receptors assembled from the Caenorhabditis elegans (C. elegans) GluClα (GLC-1) subunit can inherently respond to IVM but not to glutamate (the neurotransmitter). In contrast, heteromeric GluClα/β (GLC-1/GLC-2) assemblies respond to both ligands, independently of each other. Glutamate and IVM bind at the interface between adjacent subunits, far away from each other; glutamate in the extracellular ligand-binding domain, and IVM in the ion-channel pore periphery. To understand the importance of putative intersubunit contacts located outside the glutamate and IVM binding sites, we introduced mutations at intersubunit interfaces, between these two binding-site types. Then, we determined the effect of these mutations on the activation of the heteromeric mutant receptors by glutamate and IVM. Amongst these mutations, we characterized an α-subunit point mutation located close to the putative IVM-binding pocket, in the extracellular end of the first transmembrane helix (M1). This mutation (αF276A) moderately reduced the sensitivity of the heteromeric GluClαF276A/βWT receptor to glutamate, and slightly decreased the receptor subunits’ cooperativity in response to glutamate. In contrast, the αF276A mutation drastically reduced the sensitivity of the receptor to IVM and significantly increased the receptor subunits’ cooperativity in response to IVM. We suggest that this mutation reduces the efficacy of channel gating, and impairs the integrity of the IVM-binding pocket, likely by disrupting important interactions between the tip of M1 and the M2-M3 loop of an adjacent subunit. We hypothesize that this physical contact between M1 and the M2-M3 loop tunes the relative orientation of the ion-channel transmembrane helices M1, M2 and M3 to optimize pore opening. Interestingly, pre-exposure of the GluClαF276A/βWT mutant receptor to subthreshold IVM concentration recovered the receptor sensitivity to glutamate. We infer that IVM likely retained its positive modulation activity by constraining the transmembrane helices in a preopen orientation sensitive to glutamate, with no need for the aforementioned disrupted interactions between M1 and the M2-M3 loop.
Collapse
Affiliation(s)
- Nurit Degani-Katzav
- Laboratory of Ion Channels, The Mina and Everard Goodman Faculty of Life Sciences, Institute of Nanotechnology and Advanced Materials, Bar-Ilan UniversityRamat Gan, Israel
| | - Revital Gortler
- Laboratory of Ion Channels, The Mina and Everard Goodman Faculty of Life Sciences, Institute of Nanotechnology and Advanced Materials, Bar-Ilan UniversityRamat Gan, Israel
| | - Marina Weissman
- Laboratory of Ion Channels, The Mina and Everard Goodman Faculty of Life Sciences, Institute of Nanotechnology and Advanced Materials, Bar-Ilan UniversityRamat Gan, Israel
| | - Yoav Paas
- Laboratory of Ion Channels, The Mina and Everard Goodman Faculty of Life Sciences, Institute of Nanotechnology and Advanced Materials, Bar-Ilan UniversityRamat Gan, Israel
| |
Collapse
|
29
|
Islam R, Zhang Y, Xu L, Sah P, Lynch JW. A Chemogenetic Receptor That Enhances the Magnitude and Frequency of Glycinergic Inhibitory Postsynaptic Currents without Inducing a Tonic Chloride Flux. ACS Chem Neurosci 2017; 8:460-467. [PMID: 27958714 DOI: 10.1021/acschemneuro.6b00382] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The gene transfer-mediated expression of inhibitory ion channels in nociceptive neurons holds promise for treating intractable pain. Chemogenetics, which involves expressing constructs activated by biologically inert molecules, is of particular interest as it permits tunable neuromodulation. However, current chloride-permeable chemogenetic constructs are problematic as they mediate a tonic chloride influx which over time would deplete the chloride electrochemical gradient and reduce inhibitory efficacy. Inflammatory pain sensitization can be caused by prostaglandin E2-mediated inhibition of glycinergic inhibitory postsynaptic currents in spinal nociceptive neurons. We developed a highly conducting (100 pS) inhibitory chemogenetic construct based on a human glycine receptor (α1Y279F,A288G) with high ivermectin sensitivity. When virally infected into spinal neurons, 10 nM ivermectin increased the magnitude and frequency of glycinergic postsynaptic currents without activating a tonic chloride flux. The construct should thus produce analgesia. Its human origin and the well-established biocompatibility of its ligand suggest it may be suited to human use.
Collapse
Affiliation(s)
- Robiul Islam
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Yan Zhang
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Li Xu
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Pankaj Sah
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Joseph W. Lynch
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
30
|
Lynch JW, Zhang Y, Talwar S, Estrada-Mondragon A. Glycine Receptor Drug Discovery. ADVANCES IN PHARMACOLOGY 2017; 79:225-253. [DOI: 10.1016/bs.apha.2017.01.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
31
|
Islam R, Keramidas A, Xu L, Durisic N, Sah P, Lynch JW. Ivermectin-Activated, Cation-Permeable Glycine Receptors for the Chemogenetic Control of Neuronal Excitation. ACS Chem Neurosci 2016; 7:1647-1657. [PMID: 27611437 DOI: 10.1021/acschemneuro.6b00168] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The ability to control neuronal activation is rapidly advancing our understanding of brain function and is widely viewed as having eventual therapeutic application. Although several highly effective optogenetic, optochemical genetic, and chemogenetic techniques have been developed for this purpose, new approaches may provide better solutions for addressing particular questions and would increase the number of neuronal populations that can be controlled independently. An early chemogenetic neuronal silencing method employed a glutamate receptor Cl- channel engineered for activation by 1-3 nM ivermectin. This construct has been validated in vivo. Here, we sought to develop cation-permeable ivermectin-gated receptors that were either maximally Ca2+-permeable so as to induce neuro-excitotoxic cell death or minimally Ca2+-permeable so as to depolarize neurons with minimal excitotoxic risk. Our constructs were based on the human α1 glycine receptor Cl- channel due to its high conductance, human origin, high ivermectin sensitivity (once mutated), and because pore mutations that render it permeable to Na+ alone or Na+ plus Ca2+ are well characterized. We developed a Ca2+-impermeable excitatory receptor by introducing the F207A/P-2'Δ/A-1'E/T13'V/A288G mutations and a Ca2+-permeable excitatory receptor by introducing the F207A/A-1'E/A288G mutations. The latter receptor efficiently induces cell death and strongly depolarizes neurons at nanomolar ivermectin concentrations.
Collapse
Affiliation(s)
- Robiul Islam
- Queensland
Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Angelo Keramidas
- Queensland
Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Li Xu
- Queensland
Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Nela Durisic
- Queensland
Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Pankaj Sah
- Queensland
Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Joseph W. Lynch
- Queensland
Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
- School
of Biomedical Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
32
|
Obenhaus HA, Rozov A, Bertocchi I, Tang W, Kirsch J, Betz H, Sprengel R. Causal Interrogation of Neuronal Networks and Behavior through Virally Transduced Ivermectin Receptors. Front Mol Neurosci 2016; 9:75. [PMID: 27625595 PMCID: PMC5004486 DOI: 10.3389/fnmol.2016.00075] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 08/10/2016] [Indexed: 01/14/2023] Open
Abstract
The causal interrogation of neuronal networks involved in specific behaviors requires the spatially and temporally controlled modulation of neuronal activity. For long-term manipulation of neuronal activity, chemogenetic tools provide a reasonable alternative to short-term optogenetic approaches. Here we show that virus mediated gene transfer of the ivermectin (IVM) activated glycine receptor mutant GlyRα1AG can be used for the selective and reversible silencing of specific neuronal networks in mice. In the striatum, dorsal hippocampus, and olfactory bulb, GlyRα1AG promoted IVM dependent effects in representative behavioral assays. Moreover, GlyRα1AG mediated silencing had a strong and reversible impact on neuronal ensemble activity and c-Fos activation in the olfactory bulb. Together our results demonstrate that long-term, reversible and re-inducible neuronal silencing via GlyRα1AG is a promising tool for the interrogation of network mechanisms underlying the control of behavior and memory formation.
Collapse
Affiliation(s)
- Horst A Obenhaus
- Sprengel Research Group, Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Andrei Rozov
- OpenLab of Neurobiology, Kazan Federal UniversityKazan, Russia; Division of Neuro- and Sensory Physiology, Institute of Physiology and Pathophysiology, Heidelberg UniversityHeidelberg, Germany
| | - Ilaria Bertocchi
- Sprengel Research Group, Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Wannan Tang
- Sprengel Research Group, Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Joachim Kirsch
- Department of Medical Cell Biology, Institute for Anatomy and Cell Biology, Heidelberg University Heidelberg, Germany
| | - Heinrich Betz
- Department of Molecular Neurobiology, Max Planck Institute for Medical Research Heidelberg, Germany
| | - Rolf Sprengel
- Sprengel Research Group, Department of Molecular Neurobiology, Max Planck Institute for Medical ResearchHeidelberg, Germany; Department of Medical Cell Biology, Institute for Anatomy and Cell Biology, Heidelberg UniversityHeidelberg, Germany
| |
Collapse
|
33
|
Zhao R, Grunke SD, Keralapurath MM, Yetman MJ, Lam A, Lee TC, Sousounis K, Jiang Y, Swing DA, Tessarollo L, Ji D, Jankowsky JL. Impaired Recall of Positional Memory following Chemogenetic Disruption of Place Field Stability. Cell Rep 2016; 16:793-804. [PMID: 27373150 PMCID: PMC4956499 DOI: 10.1016/j.celrep.2016.06.032] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 03/03/2016] [Accepted: 06/03/2016] [Indexed: 11/06/2022] Open
Abstract
The neural network of the temporal lobe is thought to provide a cognitive map of our surroundings. Functional analysis of this network has been hampered by coarse tools that often result in collateral damage to other circuits. We developed a chemogenetic system to temporally control electrical input into the hippocampus. When entorhinal input to the perforant path was acutely silenced, hippocampal firing patterns became destabilized and underwent extensive remapping. We also found that spatial memory acquired prior to neural silencing was impaired by loss of input through the perforant path. Together, our experiments show that manipulation of entorhinal activity destabilizes spatial coding and disrupts spatial memory. Moreover, we introduce a chemogenetic model for non-invasive neuronal silencing that offers multiple advantages over existing strategies in this setting.
Collapse
Affiliation(s)
- Rong Zhao
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Stacy D Grunke
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Michael J Yetman
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Alexander Lam
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Cognitive Science, Rice University, Houston, TX 77251, USA
| | - Tang-Cheng Lee
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Yongying Jiang
- Institute for Applied Cancer Science, The University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA
| | - Deborah A Swing
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Lino Tessarollo
- Mouse Cancer Genetics Program, Center for Cancer Research, National Cancer Institute, Frederick, MD 21702, USA
| | - Daoyun Ji
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Joanna L Jankowsky
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA; Department of Neurosurgery, Baylor College of Medicine, Houston, TX 77030, USA; Huffington Center on Aging, Baylor College of Medicine, Houston, TX 77030, USA.
| |
Collapse
|
34
|
Braun N, Lynagh T, Yu R, Biggin PC, Pless SA. Role of an Absolutely Conserved Tryptophan Pair in the Extracellular Domain of Cys-Loop Receptors. ACS Chem Neurosci 2016; 7:339-48. [PMID: 26764897 DOI: 10.1021/acschemneuro.5b00298] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Cys-loop receptors mediate fast synaptic transmission in the nervous system, and their dysfunction is associated with a number of diseases. While some sequence variability is essential to ensure specific recognition of a chemically diverse set of ligands, other parts of the underlying amino acid sequences show a high degree of conservation, possibly to preserve the overall structural fold across the protein family. In this study, we focus on the only two absolutely conserved residues across the Cys-loop receptor family, two Trp side chains in the WXD motif of Loop D and in the WXPD motif of Loop A. Using a combination of conventional mutagenesis, unnatural amino acid incorporation, immunohistochemistry and MD simulations, we demonstrate the crucial contributions of these two Trp residues to receptor expression and function in two prototypical Cys-loop receptors, the anion-selective GlyR α1 and the cation-selective nAChR α7. Specifically, our results rule out possible electrostatic contributions of these Trp side chains and instead suggest that the overall size and shape of this aromatic pair is required in stabilizing the Cys-loop receptor extracellular domain.
Collapse
Affiliation(s)
- Nina Braun
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Timothy Lynagh
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| | - Rilei Yu
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Philip C. Biggin
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
| | - Stephan A. Pless
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen 2100, Denmark
| |
Collapse
|
35
|
Li B, Tadross MR, Tsien RW. Sequential ionic and conformational signaling by calcium channels drives neuronal gene expression. Science 2016; 351:863-7. [PMID: 26912895 DOI: 10.1126/science.aad3647] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Voltage-gated CaV1.2 channels (L-type calcium channel α1C subunits) are critical mediators of transcription-dependent neural plasticity. Whether these channels signal via the influx of calcium ion (Ca(2+)), voltage-dependent conformational change (VΔC), or a combination of the two has thus far been equivocal. We fused CaV1.2 to a ligand-gated Ca(2+)-permeable channel, enabling independent control of localized Ca(2+) and VΔC signals. This revealed an unexpected dual requirement: Ca(2+) must first mobilize actin-bound Ca(2+)/calmodulin-dependent protein kinase II, freeing it for subsequent VΔC-mediated accumulation. Neither signal alone sufficed to activate transcription. Signal order was crucial: Efficiency peaked when Ca(2+) preceded VΔC by 10 to 20 seconds. CaV1.2 VΔC synergistically augmented signaling by N-methyl-d-aspartate receptors. Furthermore, VΔC mistuning correlated with autistic symptoms in Timothy syndrome. Thus, nonionic VΔC signaling is vital to the function of CaV1.2 in synaptic and neuropsychiatric processes.
Collapse
Affiliation(s)
- Boxing Li
- Department of Neuroscience and Physiology and New York University Neuroscience Institute, New York, NY 10016, USA
| | - Michael R Tadross
- Department of Molecular and Cellular Physiology, Beckman Center, School of Medicine, Stanford University, Stanford, CA 94305, USA. Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA.
| | - Richard W Tsien
- Department of Neuroscience and Physiology and New York University Neuroscience Institute, New York, NY 10016, USA. Department of Molecular and Cellular Physiology, Beckman Center, School of Medicine, Stanford University, Stanford, CA 94305, USA
| |
Collapse
|
36
|
Kibaly C, Loh H, Law PY. A Mechanistic Approach to the Development of Gene Therapy for Chronic Pain. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 327:89-161. [DOI: 10.1016/bs.ircmb.2016.06.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
37
|
Glycine receptor mechanism elucidated by electron cryo-microscopy. Nature 2015; 526:224-9. [PMID: 26344198 DOI: 10.1038/nature14853] [Citation(s) in RCA: 305] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/23/2015] [Indexed: 12/12/2022]
Abstract
The strychnine-sensitive glycine receptor (GlyR) mediates inhibitory synaptic transmission in the spinal cord and brainstem and is linked to neurological disorders, including autism and hyperekplexia. Understanding of molecular mechanisms and pharmacology of glycine receptors has been hindered by a lack of high-resolution structures. Here we report electron cryo-microscopy structures of the zebrafish α1 GlyR with strychnine, glycine, or glycine and ivermectin (glycine/ivermectin). Strychnine arrests the receptor in an antagonist-bound closed ion channel state, glycine stabilizes the receptor in an agonist-bound open channel state, and the glycine/ivermectin complex adopts a potentially desensitized or partially open state. Relative to the glycine-bound state, strychnine expands the agonist-binding pocket via outward movement of the C loop, promotes rearrangement of the extracellular and transmembrane domain 'wrist' interface, and leads to rotation of the transmembrane domain towards the pore axis, occluding the ion conduction pathway. These structures illuminate the GlyR mechanism and define a rubric to interpret structures of Cys-loop receptors.
Collapse
|
38
|
LOBIKIN MARIA, PARÉ JEANFRAN, KAPLAN DAVIDL, LEVIN MICHAEL. Selective depolarization of transmembrane potential alters muscle patterning and muscle cell localization in Xenopus laevis embryos. THE INTERNATIONAL JOURNAL OF DEVELOPMENTAL BIOLOGY 2015; 59:303-11. [PMID: 26198143 PMCID: PMC10461602 DOI: 10.1387/ijdb.150198ml] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The correct anatomical placement and precise determination of specific cell types is required for the establishment of normal embryonic patterning. Understanding these processes is also important for progress in regenerative medicine and cancer biology. Transmembrane voltage gradients across embryonic tissues can mediate cellular communication to regulate the processes of proliferation, migration, and differentiation. Our past work showed that selective depolarization of an endogenous instructor cell population in Xenopus laevis in vivo induced a melanoma-like phenotype in the absence of genetic damage. Here, we use a hypersensitive glycine-gated chloride channel (GlyR) under control of tissue-specific promoters to show that instructor cells resident within muscle are more effective at triggering the metastatic conversion of ectodermal melanocytes than those similar cells within the nervous system. Moreover, depolarization of muscle cells results in aberrant muscle patterning and the appearance of cells expressing muscle markers within the neural tube, which impacts but does not abolish the animals' ability to learn in an associative conditioning assay. Taken together, our data reveal new details of long-range (non-cell-autonomous) reprogramming of cell behavior via alteration of the resting potential of specific embryonic subpopulations.
Collapse
Affiliation(s)
- MARIA LOBIKIN
- Center for Regenerative and Developmental Biology and Department of Biology, Tufts University, Medford, MA, USA
| | - JEAN-FRANçOIS PARÉ
- Center for Regenerative and Developmental Biology and Department of Biology, Tufts University, Medford, MA, USA
| | - DAVID L. KAPLAN
- Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - MICHAEL LEVIN
- Center for Regenerative and Developmental Biology and Department of Biology, Tufts University, Medford, MA, USA
| |
Collapse
|
39
|
Zemkova H, Tvrdonova V, Bhattacharya A, Jindrichova M. Allosteric modulation of ligand gated ion channels by ivermectin. Physiol Res 2014; 63 Suppl 1:S215-24. [PMID: 24564661 DOI: 10.33549/physiolres.932711] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Ivermectin acts as a positive allosteric regulator of several ligand-gated channels including the glutamate-gated chloride channel (GluCl), gamma aminobutyric acid type-A receptor, glycine receptor, neuronal alpha7-nicotinic receptor and purinergic P2X4 receptor. In most of the ivermectin-sensitive channels, the effects of ivermectin include the potentiation of agonist-induced currents at low concentrations and channel opening at higher concentrations. Based on mutagenesis, electrophysiological recordings and functional analysis of chimeras between ivermectin-sensitive and ivermectin-insensitive receptors, it has been concluded that ivermectin acts by insertion between transmembrane helices. The three-dimensional structure of C. elegans GluCl complexed with ivermectin has revealed the details of the ivermectin-binding site, however, no generic motif of amino acids could accurately predict ivermectin binding site for other ligand gated channels. Here, we will review what is currently known about ivermectin binding and modulation of Cys-loop receptor family of ligand-gated ion channels and what are the critical structural determinants underlying potentiation of the P2X4 receptor channel.
Collapse
Affiliation(s)
- H Zemkova
- Department of Cellular and Molecular Neuroendocrinology and Biocev, Institute of Physiology Academy of Sciences of the Czech Republic, Prague, Czech Republic.
| | | | | | | |
Collapse
|
40
|
Glorioso JC. Herpes simplex viral vectors: late bloomers with big potential. Hum Gene Ther 2014; 25:83-91. [PMID: 24502405 DOI: 10.1089/hum.2014.2501] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Joseph C Glorioso
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine , Pittsburgh, PA 15219
| |
Collapse
|
41
|
Hu L, Lan W, Guo H, Chai GD, Huang K, Zhang L, Huang Y, Chen XF, Zhang L, Song NN, Chen L, Lang B, Wang Y, Wang QX, Zhang JB, McCaig C, Xu L, Ding YQ. A mouse line for inducible and reversible silencing of specific neurons. Mol Brain 2014; 7:68. [PMID: 25231486 PMCID: PMC4177062 DOI: 10.1186/s13041-014-0068-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 08/31/2014] [Indexed: 11/13/2022] Open
Abstract
Background Genetic methods for inducibly and reversibly inhibiting neuronal activity of specific neurons are critical for exploring the functions of neuronal circuits. The engineered human glycine receptor, called ivermectin (IVM)-gated silencing receptor (IVMR), has been shown to possess this ability in vitro. Results Here we generated a mouse line, in which the IVMR coding sequence was inserted into the ROSA26 locus downstream of a loxP-flanked STOP cassette. Specific Cre-mediated IVMR expression was revealed by mis-expression of Cre in the striatum and by crossing with several Cre lines. Behavioral alteration was observed in Rosa26-IVMR mice with unilateral striatal Cre expression after systemic administration of IVM, and it could be re-initiated when IVM was applied again. A dramatic reduction in neuron firing was recorded in IVM-treated free moving Rosa26-IVMR;Emx1-Cre mice, and neuronal excitability was reduced within minutes as shown by recording in brain slice. Conclusion This Rosa26-IVMR mouse line provides a powerful tool for exploring selective circuit functions in freely behaving mice. Electronic supplementary material The online version of this article (doi:10.1186/s13041-014-0068-8) contains supplementary material, which is available to authorized users.
Collapse
|
42
|
Abstract
Elucidating the roles of neuronal cell types for physiology and behavior is essential for understanding brain functions. Perturbation of neuron electrical activity can be used to probe the causal relationship between neuronal cell types and behavior. New genetically encoded neuron perturbation tools have been developed for remotely controlling neuron function using small molecules that activate engineered receptors that can be targeted to cell types using genetic methods. Here we describe recent progress for approaches using genetically engineered receptors that selectively interact with small molecules. Called "chemogenetics," receptors with diverse cellular functions have been developed that facilitate the selective pharmacological control over a diverse range of cell-signaling processes, including electrical activity, for molecularly defined cell types. These tools have revealed remarkably specific behavioral physiological influences for molecularly defined cell types that are often intermingled with populations having different or even opposite functions.
Collapse
Affiliation(s)
- Scott M Sternson
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147;
| | | |
Collapse
|
43
|
Lees K, Musgaard M, Suwanmanee S, Buckingham SD, Biggin P, Sattelle D. Actions of agonists, fipronil and ivermectin on the predominant in vivo splice and edit variant (RDLbd, I/V) of the Drosophila GABA receptor expressed in Xenopus laevis oocytes. PLoS One 2014; 9:e97468. [PMID: 24823815 PMCID: PMC4019635 DOI: 10.1371/journal.pone.0097468] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 04/20/2014] [Indexed: 11/18/2022] Open
Abstract
Ionotropic GABA receptors are the targets for several classes of insecticides. One of the most widely-studied insect GABA receptors is RDL (resistance to dieldrin), originally isolated from Drosophila melanogaster. RDL undergoes alternative splicing and RNA editing, which influence the potency of GABA. Most work has focussed on minority isoforms. Here, we report the first characterisation of the predominant native splice variant and RNA edit, combining functional characterisation with molecular modelling of the agonist-binding region. The relative order of agonist potency is GABA> muscimol> TACA> β-alanine. The I/V edit does not alter the potency of GABA compared to RDLbd. Docking calculations suggest that these agonists bind and activate RDLbdI/V through a similar binding mode. TACA and β-alanine are predicted to bind with lower affinity than GABA, potentially explaining their lower potency, whereas the lower potency of muscimol and isoguvacine cannot be explained structurally from the docking calculations. The A301S (resistance to dieldrin) mutation reduced the potency of antagonists picrotoxin, fipronil and pyrafluprole but the I/V edit had no measurable effect. Ivermectin suppressed responses to GABA of RDLbdI/V, RDLbd and RDLbdI/VA301S. The dieldrin resistant variant also showed reduced sensitivity to Ivermectin. This study of a highly abundant insect GABA receptor isoform will help the design of new insecticides.
Collapse
Affiliation(s)
- Kristin Lees
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Maria Musgaard
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Siros Suwanmanee
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Steven David Buckingham
- Wolfson Institute for Biomedical Research, Department of Medicine, University College London, London, United Kingdom
| | - Philip Biggin
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - David Sattelle
- Wolfson Institute for Biomedical Research, Department of Medicine, University College London, London, United Kingdom
| |
Collapse
|
44
|
Han L, Talwar S, Wang Q, Shan Q, Lynch JW. Phosphorylation of α3 glycine receptors induces a conformational change in the glycine-binding site. ACS Chem Neurosci 2013; 4:1361-70. [PMID: 23834509 DOI: 10.1021/cn400097j] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Inflammatory pain sensitization is initiated by prostaglandin-induced phosphorylation of α3 glycine receptors (GlyRs) that are specifically located in inhibitory synapses on spinal pain sensory neurons. Phosphorylation reduces the magnitude of glycinergic synaptic currents, thereby disinhibiting nociceptive neurons. Although α1 and α3 subunits are both expressed on spinal nociceptive neurons, α3 is a more promising therapeutic target as its sparse expression elsewhere implies a reduced risk of side-effects. Here we compared glycine-mediated conformational changes in α1 and α3 GlyRs to identify structural differences that might be exploited in designing α3-specific analgesics. Using voltage-clamp fluorometry, we show that glycine-mediated conformational changes in the extracellular M2-M3 domain were significantly different between the two GlyR isoforms. Using a chimeric approach, we found that structural variations in the intracellular M3-M4 domain were responsible for this difference. This prompted us to test the hypothesis that phosphorylation of S346 in α3 GlyR might also induce extracellular conformation changes. We show using both voltage-clamp fluorometry and pharmacology that Ser346 phosphorylation elicits structural changes in the α3 glycine-binding site. These results provide the first direct evidence for phosphorylation-mediated extracellular conformational changes in pentameric ligand-gated ion channels, and thus suggest new loci for investigating how phosphorylation modulates structure and function in this receptor family. More importantly, by demonstrating that phosphorylation alters α3 GlyR glycine-binding site structure, they raise the possibility of developing analgesics that selectively target inflammation-modulated GlyRs.
Collapse
Affiliation(s)
- Lu Han
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane
QLD 4072, Australia
| | - Sahil Talwar
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane
QLD 4072, Australia
| | - Qian Wang
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane
QLD 4072, Australia
| | - Qiang Shan
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane
QLD 4072, Australia
| | - Joseph W. Lynch
- Queensland Brain Institute and ‡School of Biomedical Sciences, The University of Queensland, Brisbane
QLD 4072, Australia
| |
Collapse
|
45
|
Frazier SJ, Cohen BN, Lester HA. An engineered glutamate-gated chloride (GluCl) channel for sensitive, consistent neuronal silencing by ivermectin. J Biol Chem 2013; 288:21029-21042. [PMID: 23720773 DOI: 10.1074/jbc.m112.423921] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A modified invertebrate glutamate-gated Cl(-) channel (GluCl αβ) was previously employed to allow pharmacologically induced silencing of electrical activity in CNS neurons upon exposure to the anthelmintic drug ivermectin (IVM). Usefulness of the previous receptor was limited by 1) the high concentration of IVM necessary to elicit a consistent silencing phenotype, raising concern about potential side effects, and 2) the variable extent of neuronal spike suppression, due to variations in the co-expression levels of the fluorescent protein-tagged α and β subunits. To address these issues, mutant receptors generated via rational protein engineering strategies were examined for improvement. Introduction of a gain-of-function mutation (L9'F) in the second transmembrane domain of the α subunit appears to facilitate β subunit incorporation and substantially increase heteromeric GluCl αβ sensitivity to IVM. Removal of an arginine-based endoplasmic reticulum retention motif (RSR mutated to AAA) from the intracellular loop of the β subunit further promotes heteromeric expression at the plasma membrane possibly by preventing endoplasmic reticulum-associated degradation of the β subunit rather than simply reducing endoplasmic reticulum retention. A monomeric XFP (mXFP) mutation that prevents fluorescent protein dimerization complements the mutant channel effects. Expression of the newly engineered GluCl opt α-mXFP L9'F + opt β-mXFP Y182F RSR_AAA receptor in dissociated neuronal cultures markedly increases conductance and reduces variability in spike suppression at 1 nm IVM. This receptor, named "GluClv2.0," is an improved tool for IVM-induced silencing.
Collapse
Affiliation(s)
- Shawnalea J Frazier
- From the Biochemistry and Molecular Biophysics Option and; the Division of Biology, California Institute of Technology, Pasadena, California 91125
| | - Bruce N Cohen
- the Division of Biology, California Institute of Technology, Pasadena, California 91125
| | - Henry A Lester
- the Division of Biology, California Institute of Technology, Pasadena, California 91125.
| |
Collapse
|
46
|
Puinean AM, Lansdell SJ, Collins T, Bielza P, Millar NS. A nicotinic acetylcholine receptor transmembrane point mutation (G275E) associated with resistance to spinosad in Frankliniella occidentalis. J Neurochem 2013; 124:590-601. [PMID: 23016960 PMCID: PMC3644170 DOI: 10.1111/jnc.12029] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 09/24/2012] [Indexed: 12/20/2022]
Abstract
High levels of resistance to spinosad, a macrocyclic lactone insecticide, have been reported previously in western flower thrips, Frankliniella occidentalis, an economically important insect pest of vegetables, fruit and ornamental crops. We have cloned the nicotinic acetylcholine receptor (nAChR) α6 subunit from F. occidentalis (Foα6) and compared the nucleotide sequence of Foα6 from susceptible and spinosad-resistant insect populations (MLFOM and R1S respectively). A single nucleotide change has been identified in Foα6, resulting in the replacement of a glycine (G) residue in susceptible insects with a glutamic acid (E) in resistant insects. The resistance-associated mutation (G275E) is predicted to lie at the top of the third α-helical transmembrane domain of Foα6. Although there is no direct evidence identifying the location of the spinosad binding site, the analogous amino acid in the C. elegans glutamate-gated chloride channel lies in close proximity (4.4 Å) to the known binding site of ivermectin, another macrocyclic lactone pesticide. The functional consequences of the resistance-associated mutation have been examined in the human nAChR α7 subunit. Introduction of an analogous (A272E) mutation in α7 abolishes the modulatory effects of spinosad whilst having no significant effect upon activation by acetylcholine, consistent with spinosad having an allosteric mechanism of action.
Collapse
Affiliation(s)
- Alin M Puinean
- Department of Neuroscience, Physiology & Pharmacology, University College London, London, UK
| | | | | | | | | |
Collapse
|
47
|
Lobikin M, Chernet B, Lobo D, Levin M. Resting potential, oncogene-induced tumorigenesis, and metastasis: the bioelectric basis of cancer in vivo. Phys Biol 2012. [PMID: 23196890 DOI: 10.1088/1478-3975/9/6/065002] [Citation(s) in RCA: 113] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Cancer may result from localized failure of instructive cues that normally orchestrate cell behaviors toward the patterning needs of the organism. Steady-state gradients of transmembrane voltage (V(mem)) in non-neural cells are instructive, epigenetic signals that regulate pattern formation during embryogenesis and morphostatic repair. Here, we review molecular data on the role of bioelectric cues in cancer and present new findings in the Xenopus laevis model on how the microenvironment's biophysical properties contribute to cancer in vivo. First, we investigated the melanoma-like phenotype arising from serotonergic signaling by 'instructor' cells-a cell population that is able to induce a metastatic phenotype in normal melanocytes. We show that when these instructor cells are depolarized, blood vessel patterning is disrupted in addition to the metastatic phenotype induced in melanocytes. Surprisingly, very few instructor cells need to be depolarized for the hyperpigmentation phenotype to occur; we present a model of antagonistic signaling by serotonin receptors that explains the unusual all-or-none nature of this effect. In addition to the body-wide depolarization-induced metastatic phenotype, we investigated the bioelectrical properties of tumor-like structures induced by canonical oncogenes and cancer-causing compounds. Exposure to carcinogen 4-nitroquinoline 1-oxide (4NQO) induces localized tumors, but has a broad (and variable) effect on the bioelectric properties of the whole body. Tumors induced by oncogenes show aberrantly high sodium content, representing a non-invasive diagnostic modality. Importantly, depolarized transmembrane potential is not only a marker of cancer but is functionally instructive: susceptibility to oncogene-induced tumorigenesis is significantly reduced by forced prior expression of hyperpolarizing ion channels. Importantly, the same effect can be achieved by pharmacological manipulation of endogenous chloride channels, suggesting a strategy for cancer suppression that does not require gene therapy. Together, these data extend our understanding of the recently demonstrated role of transmembrane potential in tumor formation and metastatic cell behavior. V(mem) is an important non-genetic biophysical aspect of the microenvironment that regulates the balance between normally patterned growth and carcinogenesis.
Collapse
Affiliation(s)
- Maria Lobikin
- Biology Department and Tufts Center for Regenerative and Developmental Biology, Tufts University, 200 Boston Avenue, Medford, MA 02155, USA
| | | | | | | |
Collapse
|
48
|
Goins WF, Cohen JB, Glorioso JC. Gene therapy for the treatment of chronic peripheral nervous system pain. Neurobiol Dis 2012; 48:255-70. [PMID: 22668775 DOI: 10.1016/j.nbd.2012.05.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 05/11/2012] [Accepted: 05/24/2012] [Indexed: 11/30/2022] Open
Abstract
Chronic pain is a major health concern affecting 80 million Americans at some time in their lives with significant associated morbidity and effects on individual quality of life. Chronic pain can result from a variety of inflammatory and nerve damaging events that include cancer, infectious diseases, autoimmune-related syndromes and surgery. Current pharmacotherapies have not provided an effective long-term solution as they are limited by drug tolerance and potential abuse. These concerns have led to the development and testing of gene therapy approaches to treat chronic pain. The potential efficacy of gene therapy for pain has been reported in numerous pre-clinical studies that demonstrate pain control at the level of the spinal cord. This promise has been recently supported by a Phase-I human trial in which a replication-defective herpes simplex virus (HSV) vector was used to deliver the human pre-proenkephalin (hPPE) gene, encoding the natural opioid peptides met- and leu-enkephalin (ENK), to cancer patients with intractable pain resulting from bone metastases (Fink et al., 2011). The study showed that the therapy was well tolerated and that patients receiving the higher doses of therapeutic vector experienced a substantial reduction in their overall pain scores for up to a month post vector injection. These exciting early clinical results await further patient testing to demonstrate treatment efficacy and will likely pave the way for other gene therapies to treat chronic pain.
Collapse
Affiliation(s)
- William F Goins
- Dept of Microbiology & Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh PA 15219, USA.
| | | | | |
Collapse
|
49
|
Lynagh T, Lynch JW. Molecular mechanisms of Cys-loop ion channel receptor modulation by ivermectin. Front Mol Neurosci 2012; 5:60. [PMID: 22586367 PMCID: PMC3345530 DOI: 10.3389/fnmol.2012.00060] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 04/17/2012] [Indexed: 11/13/2022] Open
Abstract
Ivermectin is an anthelmintic drug that works by inhibiting neuronal activity and muscular contractility in arthropods and nematodes. It works by activating glutamate-gated chloride channels (GluClRs) at nanomolar concentrations. These receptors, found exclusively in invertebrates, belong to the pentameric Cys-loop receptor family of ligand-gated ion channels (LGICs). Higher (micromolar) concentrations of ivermectin also activate or modulate vertebrate Cys-loop receptors, including the excitatory nicotinic and the inhibitory GABA type-A and glycine receptors (GlyRs). An X-ray crystal structure of ivermectin complexed with the C. elegans α GluClR demonstrated that ivermectin binds to the transmembrane domain in a cleft at the interface of adjacent subunits. It also identified three hydrogen bonds thought to attach ivermectin to its site. Site-directed mutagenesis and voltage-clamp electrophysiology have also been employed to probe the binding site for ivermectin in α1 GlyRs. These have raised doubts as to whether the hydrogen bonds are essential for high ivermectin potency. Due to its lipophilic nature, it is likely that ivermectin accumulates in the membrane and binds reversibly (i.e., weakly) to its site. Several lines of evidence suggest that ivermectin opens the channel pore via a structural change distinct from that induced by the neurotransmitter agonist. Conformational changes occurring at locations distant from the pore can be probed using voltage-clamp fluorometry (VCF), a technique which involves quantitating agonist-induced fluorescence changes from environmentally sensitive fluorophores covalently attached to receptor domains of interest. This technique has demonstrated that ivermectin induces a global conformational change that propagates from the transmembrane domain to the neurotransmitter binding site, thus suggesting a mechanism by which ivermectin potentiates neurotransmitter-gated currents. Together, this information provides new insights into the mechanisms of action of this important drug.
Collapse
Affiliation(s)
- Timothy Lynagh
- Queensland Brain Institute, The University of Queensland, Brisbane QLD, Australia
| | | |
Collapse
|
50
|
Wolstenholme AJ. Ion channels and receptor as targets for the control of parasitic nematodes. Int J Parasitol Drugs Drug Resist 2011; 1:2-13. [PMID: 24533259 PMCID: PMC3898135 DOI: 10.1016/j.ijpddr.2011.09.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 09/14/2011] [Accepted: 09/21/2011] [Indexed: 01/19/2023]
Abstract
Many of the anthelmintic drugs in use today act on the nematode nervous system. Ion channel targets have some obvious advantages. They tend to act quickly, which means that they will clear many infections rapidly. They produce very obvious effects on the worms, typically paralyzing them, and these effects are suitable for use in rapid and high-throughput assays. Many of the ion channels and enzymes targeted can also be incorporated into such assays. The macrocyclic lactones bind to an allosteric site on glutamate-gated chloride channels, either directly activating the channel or enhancing the effect of the normal agonist, glutamate. Many old and new anthelmintics, including tribendimidine and the amino-acetonitrile derivatives, act as agonists at nicotinic acetylcholine receptors; derquantel is an antagonist at these receptors. Nematodes express many different types of nicotinic receptor and this diversity means that they are likely to remain important targets for the foreseeable future. Emodepside may have multiple effects, affecting both a potassium channel and a pre-synaptic G protein-coupled receptor; although few other current drugs act at such targets, this example indicates that they may be more important in the future. The nematode nervous system contains many other ion channels and receptors that have not so far been exploited in worm control but which should be explored in the development of effective new compounds.
Collapse
Affiliation(s)
- Adrian J. Wolstenholme
- Dept. of Infectious Diseases and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| |
Collapse
|