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Changeux JP. [Working with François Gros at the Institut Pasteur: allostery, the nicotinic receptor and the biology of the future]. C R Biol 2024; 346:9-13. [PMID: 38131160 DOI: 10.5802/crbiol.143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2023] [Accepted: 11/06/2023] [Indexed: 12/23/2023]
Abstract
Working with François Gros was a privileged moment in my scientific life, enabling me to appreciate a scientific personality whose generosity knew no bounds and whose vision of science was far ahead of its time.
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2
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Burke SM, Avstrikova M, Noviello CM, Mukhtasimova N, Changeux JP, Thakur GA, Sine SM, Cecchini M, Hibbs RE. Structural mechanisms of α7 nicotinic receptor allosteric modulation and activation. Cell 2024; 187:1160-1176.e21. [PMID: 38382524 PMCID: PMC10950261 DOI: 10.1016/j.cell.2024.01.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 12/05/2023] [Accepted: 01/22/2024] [Indexed: 02/23/2024]
Abstract
The α7 nicotinic acetylcholine receptor is a pentameric ligand-gated ion channel that plays an important role in cholinergic signaling throughout the nervous system. Its unique physiological characteristics and implications in neurological disorders and inflammation make it a promising but challenging therapeutic target. Positive allosteric modulators overcome limitations of traditional α7 agonists, but their potentiation mechanisms remain unclear. Here, we present high-resolution structures of α7-modulator complexes, revealing partially overlapping binding sites but varying conformational states. Structure-guided functional and computational tests suggest that differences in modulator activity arise from the stable rotation of a channel gating residue out of the pore. We extend the study using a time-resolved cryoelectron microscopy (cryo-EM) approach to reveal asymmetric state transitions for this homomeric channel and also find that a modulator with allosteric agonist activity exploits a distinct channel-gating mechanism. These results define mechanisms of α7 allosteric modulation and activation with implications across the pentameric receptor superfamily.
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Affiliation(s)
- Sean M Burke
- Molecular Biophysics Graduate Program, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mariia Avstrikova
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, 67081 Strasbourg Cedex, France
| | - Colleen M Noviello
- Department of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nuriya Mukhtasimova
- Receptor Biology Laboratory, Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55902, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN 55902, USA
| | - Jean-Pierre Changeux
- Neuroscience Department, Institut Pasteur, Collège de France, 75015 Paris, France
| | - Ganesh A Thakur
- Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA
| | - Steven M Sine
- Receptor Biology Laboratory, Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, MN 55902, USA; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, MN 55902, USA; Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55902, USA.
| | - Marco Cecchini
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, 67081 Strasbourg Cedex, France.
| | - Ryan E Hibbs
- Department of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
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3
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Farisco M, Changeux JP. About the compatibility between the perturbational complexity index and the global neuronal workspace theory of consciousness. Neurosci Conscious 2023; 2023:niad016. [PMID: 37342235 PMCID: PMC10279414 DOI: 10.1093/nc/niad016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 04/18/2023] [Accepted: 05/31/2023] [Indexed: 06/22/2023] Open
Abstract
This paper investigates the compatibility between the theoretical framework of the global neuronal workspace theory (GNWT) of conscious processing and the perturbational complexity index (PCI). Even if it has been introduced within the framework of a concurrent theory (i.e. Integrated Information Theory), PCI appears, in principle, compatible with the main tenet of GNWT, which is a conscious process that depends on a long-range connection between different cortical regions, more specifically on the amplification, global propagation, and integration of brain signals. Notwithstanding this basic compatibility, a number of limited compatibilities and apparent differences emerge. This paper starts from the description of brain complexity, a notion that is crucial for PCI, to then summary of the main features of PCI and the main tenets of GNWT. Against this background, the text explores the compatibility between PCI and GNWT. It concludes that GNWT and PCI are fundamentally compatible, even though there are some partial disagreements and some points to further examine.
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Affiliation(s)
- Michele Farisco
- *Corresponding author. Centre for Research Ethics & Bioethics (CRB), Uppsala University, Box 564, Uppsala SE-751 22. E-mail:
| | - Jean-Pierre Changeux
- Neuroscience Department, Institut Pasteur, 25-28 Rue du Dr Roux, Paris 75015, France
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4
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Hublin JJ, Changeux JP. Paleoanthropology of cognition: an overview on Hominins brain evolution. C R Biol 2022; 345:57-75. [PMID: 36847465 DOI: 10.5802/crbiol.92] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 10/03/2022] [Indexed: 11/07/2022]
Abstract
Recent advances in neurobiology, paleontology, and paleogenetics allow us to associate changes in brain size and organization with three main "moments" of increased behavioral complexity and, more speculatively, language development. First, Australopiths display a significant increase in brain size relative to the great apes and an incipient extension of postnatal brain development. However, their cortical organization remains essentially similar to that of apes. Second, over the last 2 My, with two notable exceptions, brain size increases dramatically, partly in relation to changes in body size. Differential enlargements and reorganizations of cortical areas lay the foundation for the "language-ready" brain and cumulative culture of later Homo species. Third, in Homo sapiens, brain size remains fairly stable over the last 300,000 years but an important cerebral reorganization takes place. It affects the frontal and temporal lobes, the parietal areas and the cerebellum and resulted in a more globular shape of the brain. These changes are associated, among others, with an increased development of long-distance-horizontal-connections. A few regulatory genetic events took place in the course of this hominization process with, in particular, enhanced neuronal proliferation and global brain connectivity.
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5
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Changeux JP. Louis Pasteur, molecular dissymmetry, therapeutic chemistry and neuropharmacology. C R Biol 2022; 345:7-20. [PMID: 36852593 DOI: 10.5802/crbiol.81] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 07/12/2022] [Indexed: 11/05/2022]
Abstract
Louis Pasteur is celebrated as the founding father of microbiology. But he was a chemist by training and discovered molecular dissymmetry experimentally. All his life, his constant preoccupation will be to apply the method and strategies of the fundamental sciences to living processes, "from the molecule to the brain". His fundamental aim will be, beyond the biology of microbes, the chemistry of life, a disposition which signs the originality of his work. More unexpectedly, Pasteur was at the origin of therapeutic chemistry-which his successors, and especially Daniel Bovet, brilliantly illustrated at the Pasteur Institute and which they would pursue with the pharmacology of the nervous system or "neuropharmacology".
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Cerdan AH, Peverini L, Changeux JP, Corringer PJ, Cecchini M. Lateral fenestrations in the extracellular domain of the glycine receptor contribute to the main chloride permeation pathway. Sci Adv 2022; 8:eadc9340. [PMID: 36240268 PMCID: PMC9565810 DOI: 10.1126/sciadv.adc9340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 08/29/2022] [Indexed: 06/16/2023]
Abstract
Glycine receptors (GlyRs) are ligand-gated ion channels mediating signal transduction at chemical synapses. Since the early patch-clamp electrophysiology studies, the details of the ion permeation mechanism have remained elusive. Here, we combine molecular dynamics simulations of a zebrafish GlyR-α1 model devoid of the intracellular domain with mutagenesis and single-channel electrophysiology of the full-length human GlyR-α1. We show that lateral fenestrations between subunits in the extracellular domain provide the main translocation pathway for chloride ions to enter/exit a central water-filled vestibule at the entrance of the transmembrane channel. In addition, we provide evidence that these fenestrations are at the origin of current rectification in known anomalous mutants and design de novo two inward-rectifying channels by introducing mutations within them. These results demonstrate the central role of lateral fenestrations on synaptic neurotransmission.
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Affiliation(s)
- Adrien H. Cerdan
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
| | - Laurie Peverini
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
| | - Jean-Pierre Changeux
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA
- Collège de France, Paris, France
| | - Pierre-Jean Corringer
- Institut Pasteur, Université Paris Cité, CNRS UMR 3571, Channel-Receptors Unit, Paris, France
| | - Marco Cecchini
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France
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Grover D, Chen JY, Xie J, Li J, Changeux JP, Greenspan RJ. Differential mechanisms underlie trace and delay conditioning in Drosophila. Nature 2022; 603:302-308. [PMID: 35173333 DOI: 10.1038/s41586-022-04433-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 01/13/2022] [Indexed: 12/17/2022]
Abstract
Two forms of associative learning-delay conditioning and trace conditioning-have been widely investigated in humans and higher-order mammals1. In delay conditioning, an unconditioned stimulus (for example, an electric shock) is introduced in the final moments of a conditioned stimulus (for example, a tone), with both ending at the same time. In trace conditioning, a 'trace' interval separates the conditioned stimulus and the unconditioned stimulus. Trace conditioning therefore relies on maintaining a neural representation of the conditioned stimulus after its termination (hence making distraction possible2), to learn the conditioned stimulus-unconditioned stimulus contingency3; this makes it more cognitively demanding than delay conditioning4. Here, by combining virtual-reality behaviour with neurogenetic manipulations and in vivo two-photon brain imaging, we show that visual trace conditioning and delay conditioning in Drosophila mobilize R2 and R4m ring neurons in the ellipsoid body. In trace conditioning, calcium transients during the trace interval show increased oscillations and slower declines over repeated training, and both of these effects are sensitive to distractions. Dopaminergic activity accompanies signal persistence in ring neurons, and this is decreased by distractions solely during trace conditioning. Finally, dopamine D1-like and D2-like receptor signalling in ring neurons have different roles in delay and trace conditioning; dopamine D1-like receptor 1 mediates both forms of conditioning, whereas the dopamine D2-like receptor is involved exclusively in sustaining ring neuron activity during the trace interval of trace conditioning. These observations are similar to those previously reported in mammals during arousal5, prefrontal activation6 and high-level cognitive learning7,8.
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Affiliation(s)
- Dhruv Grover
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA
| | - Jen-Yung Chen
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA
| | - Jiayun Xie
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA
| | - Jinfang Li
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA
| | - Jean-Pierre Changeux
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA.,CNRS UMR 3571, Institut Pasteur, Paris, France.,College de France, Paris, France
| | - Ralph J Greenspan
- Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA, USA. .,Division of Biological Sciences, University of California, San Diego, La Jolla, CA, USA.
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8
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Taylor SS, Hunter T, Changeux JP. A tribute to Eddy Fischer (April 6, 1920-August 27, 2021): Passionate biochemist and mentor. Proc Natl Acad Sci U S A 2022; 119:e2121815119. [PMID: 35042780 PMCID: PMC8784095 DOI: 10.1073/pnas.2121815119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Susan S Taylor
- Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093-0654;
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0654
| | - Tony Hunter
- Molecular and Cell Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037
| | - Jean-Pierre Changeux
- Department of Neuroscience, Institut Pasteur, URA 2182, CNRS, Paris F-75015, France
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Hilgetag CC, Goulas A, Changeux JP. A natural cortical axis connecting the outside and inside of the human brain. Netw Neurosci 2022; 6:950-959. [PMID: 36875013 PMCID: PMC9976644 DOI: 10.1162/netn_a_00256] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 05/17/2022] [Indexed: 11/04/2022] Open
Abstract
What structural and connectivity features of the human brain help to explain the extraordinary human cognitive abilities? We recently proposed a set of relevant connectomic fundamentals, some of which arise from the size scaling of the human brain relative to other primate brains, while others of these fundamentals may be uniquely human. In particular, we suggested that the remarkable increase of the size of the human brain due to its prolonged prenatal development has brought with it an increased sparsification, hierarchical modularization, as well as increased depth and cytoarchitectonic differentiation of brain networks. These characteristic features are complemented by a shift of projection origins to the upper layers of many cortical areas as well as the significantly prolonged postnatal development and plasticity of the upper cortical layers. Another fundamental aspect of cortical organization that has emerged in recent research is the alignment of diverse features of evolution, development, cytoarchitectonics, function, and plasticity along a principal, natural cortical axis from sensory ("outside") to association ("inside") areas. Here we highlight how this natural axis is integrated in the characteristic organization of the human brain. In particular, the human brain displays a developmental expansion of outside areas and a stretching of the natural axis such that outside areas are more widely separated from each other and from inside areas than in other species. We outline some functional implications of this characteristic arrangement.
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Affiliation(s)
- Claus C Hilgetag
- Institute of Computational Neuroscience, University Medical Center Eppendorf, Hamburg University, Hamburg, Germany.,Department of Health Sciences, Boston University, Boston, MA, USA
| | - Alexandros Goulas
- Institute of Computational Neuroscience, University Medical Center Eppendorf, Hamburg University, Hamburg, Germany
| | - Jean-Pierre Changeux
- CNRS UMR 3571, Institut Pasteur, Paris, France.,Communications Cellulaires, Collège de France, Paris, France
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10
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Zhang CL, Koukouli F, Allegra M, Ortiz C, Kao HL, Maskos U, Changeux JP, Schmidt-Hieber C. Inhibitory control of synaptic signals preceding locomotion in mouse frontal cortex. Cell Rep 2021; 37:110035. [PMID: 34818555 PMCID: PMC8640223 DOI: 10.1016/j.celrep.2021.110035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 09/29/2021] [Accepted: 10/31/2021] [Indexed: 11/03/2022] Open
Abstract
The frontal cortex is essential for organizing voluntary movement. The secondary motor cortex (MOs) is a frontal subregion thought to integrate internal and external inputs before motor action. However, how excitatory and inhibitory synaptic inputs to MOs neurons are integrated preceding movement remains unclear. Here, we address this question by performing in vivo whole-cell recordings from MOs neurons of head-fixed mice moving on a treadmill. We find that principal neurons produce slowly increasing membrane potential and spike ramps preceding spontaneous running. After goal-directed training, ramps show larger amplitudes and accelerated kinetics. Chemogenetic suppression of interneurons combined with modeling suggests that the interplay between parvalbumin-positive (PV+) and somatostatin-positive (SOM+) interneurons, along with principal neuron recurrent connectivity, shape ramping signals. Plasticity of excitatory synapses on SOM+ interneurons can explain the ramp acceleration after training. Altogether, our data reveal that local interneurons differentially control task-dependent ramping signals when MOs neurons integrate inputs preceding movement.
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Affiliation(s)
- Chun-Lei Zhang
- Institut Pasteur, Université de Paris, Neural Circuits for Spatial Navigation and Memory, 75015 Paris, France.
| | - Fani Koukouli
- Institut Pasteur, Université de Paris, CNRS UMR 3571, Integrative Neurobiology of Cholinergic Systems, 75015 Paris, France; Institut Du Cerveau-Paris Brain Institute-ICM, Sorbonne Université, Inserm U1127, CNRS UMR 7225, 75013 Paris, France
| | - Manuela Allegra
- Institut Pasteur, Université de Paris, Neural Circuits for Spatial Navigation and Memory, 75015 Paris, France
| | - Cantin Ortiz
- Institut Pasteur, Université de Paris, Neural Circuits for Spatial Navigation and Memory, 75015 Paris, France; Sorbonne Université, Collège Doctoral, 75005 Paris, France
| | - Hsin-Lun Kao
- Institut Pasteur, Université de Paris, Neural Circuits for Spatial Navigation and Memory, 75015 Paris, France
| | - Uwe Maskos
- Institut Pasteur, Université de Paris, CNRS UMR 3571, Integrative Neurobiology of Cholinergic Systems, 75015 Paris, France
| | - Jean-Pierre Changeux
- Institut Pasteur, Université de Paris, Department of Neuroscience, 75015 Paris, France; Collège de France, 75005 Paris, France
| | - Christoph Schmidt-Hieber
- Institut Pasteur, Université de Paris, Neural Circuits for Spatial Navigation and Memory, 75015 Paris, France.
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11
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Cecchini M, Changeux JP. Nicotinic receptors: From protein allostery to computational neuropharmacology. Mol Aspects Med 2021; 84:101044. [PMID: 34656371 DOI: 10.1016/j.mam.2021.101044] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 11/15/2022]
Abstract
We propose an extension and further development of the Monod-Wyman-Changeux model for allosteric transitions of regulatory proteins to brain communications and specifically to neurotransmitters receptors, with the nicotinic acetylcholine receptor (nAChR) as a model of ligand-gated ion channels. The present development offers an expression of the change of the gating isomerization constant caused by pharmacological ligand binding in terms of its value in the absence of ligands and several "modulation factors", which vary with orthosteric ligand binding (agonists/antagonists), allosteric ligand binding (positive allosteric modulators/negative allosteric modulators) and receptor desensitization. The new - explicit - formulation of such "modulation factors", provides expressions for the pharmacological attributes of potency, efficacy, and selectivity for the modulatory ligands (including endogenous neurotransmitters) in terms of their binding affinity for the active, resting, and desensitized states of the receptor. The current formulation provides ways to design neuroactive compounds with a controlled pharmacological profile, opening the field of computational neuro-pharmacology.
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Affiliation(s)
- Marco Cecchini
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083, Strasbourg Cedex, France.
| | - Jean-Pierre Changeux
- Kavli Institute for Brain & Mind University of California, San Diego La Jolla, CA, 92093, USA; Institut Pasteur, URA 2182, CNRS, F-75015, France; Collège de France, F-75005 Paris, France.
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12
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Oasa S, Krmpot AJ, Nikolić SN, Clayton AHA, Tsigelny IF, Changeux JP, Terenius L, Rigler R, Vukojević V. Dynamic Cellular Cartography: Mapping the Local Determinants of Oligodendrocyte Transcription Factor 2 (OLIG2) Function in Live Cells Using Massively Parallel Fluorescence Correlation Spectroscopy Integrated with Fluorescence Lifetime Imaging Microscopy (mpFCS/FLIM). Anal Chem 2021; 93:12011-12021. [PMID: 34428029 PMCID: PMC8427561 DOI: 10.1021/acs.analchem.1c02144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
Compartmentalization
and integration of molecular
processes through diffusion are basic mechanisms through which cells
perform biological functions. To characterize these mechanisms in
live cells, quantitative and ultrasensitive analytical methods with
high spatial and temporal resolution are needed. Here, we present
quantitative scanning-free confocal microscopy with single-molecule
sensitivity, high temporal resolution (∼10 μs/frame),
and fluorescence lifetime imaging capacity, developed by integrating
massively parallel fluorescence correlation spectroscopy with fluorescence
lifetime imaging microscopy (mpFCS/FLIM); we validate the method,
use it to map in live cell location-specific variations in the concentration,
diffusion, homodimerization, DNA binding, and local environment of
the oligodendrocyte transcription factor 2 fused with the enhanced
Green Fluorescent Protein (OLIG2-eGFP), and characterize the effects
of an allosteric inhibitor of OLIG2 dimerization on these determinants
of OLIG2 function. In particular, we show that cytoplasmic OLIG2-eGFP
is largely monomeric and freely diffusing, with the fraction of freely
diffusing OLIG2-eGFP molecules being fD,freecyt = (0.75
± 0.10) and the diffusion time τD,freecyt = (0.5 ± 0.3) ms. In contrast,
OLIG2-eGFP homodimers are abundant in the cell nucleus, constituting
∼25% of the nuclear pool, some fD,boundnuc = (0.65
± 0.10) of nuclear OLIG2-eGFP is bound to chromatin DNA, whereas
freely moving OLIG2-eGFP molecules diffuse at the same rate as those
in the cytoplasm, as evident from the lateral diffusion times τD,freenuc = τD,freecyt = (0.5
± 0.3) ms. OLIG2-eGFP interactions with chromatin DNA, revealed
through their influence on the apparent diffusion behavior of OLIG2-eGFP,
τD,boundnuc (850 ± 500) ms, are characterized by an apparent dissociation
constant Kd,appOLIG2-DNA = (45 ± 30) nM. The apparent
dissociation constant of OLIG2-eGFP homodimers was estimated to be Kd,app(OLIG2-eGFP)2 ≈ 560 nM. The allosteric inhibitor of OLIG2 dimerization,
compound NSC 50467, neither affects OLIG2-eGFP properties in the cytoplasm
nor does it alter the overall cytoplasmic environment. In contrast,
it significantly impedes OLIG2-eGFP homodimerization in the cell nucleus,
increasing five-fold the apparent dissociation constant, Kd,app,NSC50467(OLIG2-eGFP)2 ≈ 3 μM, thus reducing homodimer levels to below 7%
and effectively abolishing OLIG2-eGFP specific binding to chromatin
DNA. The mpFCS/FLIM methodology has a myriad of applications in biomedical
research and pharmaceutical industry. For example, it is indispensable
for understanding how biological functions emerge through the dynamic
integration of location-specific molecular processes and invaluable
for drug development, as it allows us to quantitatively characterize
the interactions of drugs with drug targets in live cells.
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Affiliation(s)
- Sho Oasa
- Department of Clinical Neuroscience (CNS), Center for Molecular Medicine (CMM), Karolinska Institutet, 17176 Stockholm, Sweden
| | - Aleksandar J Krmpot
- Department of Clinical Neuroscience (CNS), Center for Molecular Medicine (CMM), Karolinska Institutet, 17176 Stockholm, Sweden.,Institute of Physics Belgrade, University of Belgrade, 11080 Belgrade, Serbia
| | - Stanko N Nikolić
- Department of Clinical Neuroscience (CNS), Center for Molecular Medicine (CMM), Karolinska Institutet, 17176 Stockholm, Sweden.,Institute of Physics Belgrade, University of Belgrade, 11080 Belgrade, Serbia
| | - Andrew H A Clayton
- Optical Sciences Centre, Department of Physics and Astronomy, School of Science, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Igor F Tsigelny
- Department of Neurosciences, University of California San Diego, La Jolla, California 92093-0819, United States
| | - Jean-Pierre Changeux
- Department of Neuroscience, Unité Neurobiologie Intégrative des Systèmes Cholinergiques, Institut Pasteur, F-75724 Paris 15, France
| | - Lars Terenius
- Department of Clinical Neuroscience (CNS), Center for Molecular Medicine (CMM), Karolinska Institutet, 17176 Stockholm, Sweden
| | - Rudolf Rigler
- Department of Clinical Neuroscience (CNS), Center for Molecular Medicine (CMM), Karolinska Institutet, 17176 Stockholm, Sweden.,Department of Medical Biochemistry and Biophysics (MBB), Karolinska Institutet, 17177 Stockholm, Sweden
| | - Vladana Vukojević
- Department of Clinical Neuroscience (CNS), Center for Molecular Medicine (CMM), Karolinska Institutet, 17176 Stockholm, Sweden
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13
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Chosidow O, Bernigaud C, Guillemot D, Giraudeau B, Lespine A, Changeux JP, Bourhy H, Lecuit M, Amoura Z. Ivermectin as a potential treatment for COVID-19? PLoS Negl Trop Dis 2021; 15:e0009446. [PMID: 34061842 PMCID: PMC8168910 DOI: 10.1371/journal.pntd.0009446] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 05/04/2021] [Indexed: 12/15/2022] Open
Affiliation(s)
- Olivier Chosidow
- Service de Dermatologie, Hôpital Henri Mondor, AP-HP, Université Paris-Est, Créteil, France
- Groupe de recherche Dynamyc, EA7380, Faculté de Santé de Créteil, École nationale vétérinaire d’Alfort, USC ANSES, Université Paris-Est Créteil, Créteil, France
- * E-mail:
| | - Charlotte Bernigaud
- Service de Dermatologie, Hôpital Henri Mondor, AP-HP, Université Paris-Est, Créteil, France
- Groupe de recherche Dynamyc, EA7380, Faculté de Santé de Créteil, École nationale vétérinaire d’Alfort, USC ANSES, Université Paris-Est Créteil, Créteil, France
| | - Didier Guillemot
- Université Paris-Saclay, UVSQ, Inserm, CESP, Anti-Infective Evasion and Pharmacoepidemiology Team, Montigny-Le-Bretonneux, France
- AP-HP, Paris-Saclay, Public Health, Medical Information, Clinical Research, Le Kremlin-Bicêtre, France
- Institut Pasteur, Epidemiology and Modelling of Antibiotic Evasion (EMAE), Paris, France
| | - Bruno Giraudeau
- UMR SPHERE Inserm U1246, Université de Tours, Université de Nantes, & INSERM CIC1415, CHRU de Tours, Tours, France
| | - Anne Lespine
- INTHERES, Université de Toulouse, INRAE, ENVT, Toulouse, France
| | - Jean-Pierre Changeux
- Institut Pasteur CNRS UMR 3571 Department of Neuroscience and Collège de France, Paris, France
| | - Hervé Bourhy
- Institut Pasteur, Lyssavirus epidemiology and neuropathology Unit, Paris, France
| | - Marc Lecuit
- Intitut Pasteur, Biology of Infection Unit, Inserm U1117, Paris, France
- Université de Paris, Service des Maladies Infectieuses et Tropicales, Hôpital Universitaire Necker-Enfants Malades, AP-HP, Institut Imagine, Paris, France
| | - Zahir Amoura
- Sorbonne Université, Inserm UMR-S 1135, Centre d’Immunologie et des Maladies Infectieuses (CIMI-Paris), AP-HP, Groupement hospitalier Pitié-Salpêtrière, service de médecine interne 2, Paris, France
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14
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Changeux JP, Goulas A, Hilgetag CC. A Connectomic Hypothesis for the Hominization of the Brain. Cereb Cortex 2021; 31:2425-2449. [PMID: 33367521 PMCID: PMC8023825 DOI: 10.1093/cercor/bhaa365] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/30/2020] [Accepted: 11/02/2020] [Indexed: 02/06/2023] Open
Abstract
Cognitive abilities of the human brain, including language, have expanded dramatically in the course of our recent evolution from nonhuman primates, despite only minor apparent changes at the gene level. The hypothesis we propose for this paradox relies upon fundamental features of human brain connectivity, which contribute to a characteristic anatomical, functional, and computational neural phenotype, offering a parsimonious framework for connectomic changes taking place upon the human-specific evolution of the genome. Many human connectomic features might be accounted for by substantially increased brain size within the global neural architecture of the primate brain, resulting in a larger number of neurons and areas and the sparsification, increased modularity, and laminar differentiation of cortical connections. The combination of these features with the developmental expansion of upper cortical layers, prolonged postnatal brain development, and multiplied nongenetic interactions with the physical, social, and cultural environment gives rise to categorically human-specific cognitive abilities including the recursivity of language. Thus, a small set of genetic regulatory events affecting quantitative gene expression may plausibly account for the origins of human brain connectivity and cognition.
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Affiliation(s)
- Jean-Pierre Changeux
- CNRS UMR 3571, Institut Pasteur, 75724 Paris, France
- Communications Cellulaires, Collège de France, 75005 Paris, France
| | - Alexandros Goulas
- Institute of Computational Neuroscience, University Medical Center Eppendorf, Hamburg University, 20246 Hamburg, Germany
| | - Claus C Hilgetag
- Institute of Computational Neuroscience, University Medical Center Eppendorf, Hamburg University, 20246 Hamburg, Germany
- Department of Health Sciences, Boston University, Boston, MA 02115, USA
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15
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16
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Changeux JP, Amoura Z, Rey FA, Miyara M. A nicotinic hypothesis for Covid-19 with preventive and therapeutic implications. C R Biol 2020; 343:33-39. [PMID: 32720486 DOI: 10.5802/crbiol.8] [Citation(s) in RCA: 125] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 04/18/2020] [Indexed: 01/08/2023]
Abstract
SARS-CoV-2 epidemics raises a considerable issue of public health at the planetary scale. There is a pressing urgency to find treatments based upon currently available scientific knowledge. Therefore, we tentatively propose a hypothesis which hopefully might ultimately help save lives. Based on the current scientific literature and on new epidemiological data which reveal that current smoking status appears to be a protective factor against the infection by SARS-CoV-2 [1], we hypothesize that the nicotinic acetylcholine receptor (nAChR) plays a key role in the pathophysiology of Covid-19 infection and might represent a target for the prevention and control of Covid-19 infection.
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Affiliation(s)
- Jean-Pierre Changeux
- Institut Pasteur CNRS UMR 3571 Department of Neuroscience and Collège de France, Paris France
| | - Zahir Amoura
- Sorbonne Université, Inserm UMRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris).,Assistance Publique-Hôpitaux de Paris, Groupement Hospitalier Pitié-Salpêtrière, Service de Médecine Interne 2, Maladies auto-immune et systémiques Institut E3M
| | - Felix A Rey
- Institut Pasteur, Structural Virology Unit, Department of Virology, CNRS UMR 3569, Institut Pasteur Paris France
| | - Makoto Miyara
- Sorbonne Université, Inserm UMRS, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris).,Assistance Publique-Hôpitaux de Paris, Groupement Hospitalier Pitié-Salpêtrière, Département d'Immunologie, Paris, France
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17
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Cerdan AH, Sisquellas M, Pereira G, Barreto Gomes DE, Changeux JP, Cecchini M. The Glycine Receptor Allosteric Ligands Library (GRALL). Bioinformatics 2020; 36:3379-3384. [PMID: 32163115 PMCID: PMC7267813 DOI: 10.1093/bioinformatics/btaa170] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/19/2020] [Accepted: 03/09/2020] [Indexed: 01/01/2023] Open
Abstract
MOTIVATION Glycine receptors (GlyRs) mediate fast inhibitory neurotransmission in the brain and have been recognized as key pharmacological targets for pain. A large number of chemically diverse compounds that are able to modulate GlyR function both positively and negatively have been reported, which provides useful information for the development of pharmacological strategies and models for the allosteric modulation of these ion channels. RESULTS Based on existing literature, we have collected 218 unique chemical entities with documented modulatory activities at homomeric GlyR-α1 and -α3 and built a database named GRALL. This collection includes agonists, antagonists, positive and negative allosteric modulators and a number of experimentally inactive compounds. Most importantly, for a large fraction of them a structural annotation based on their putative binding site on the receptor is provided. This type of annotation, which is currently missing in other drug banks, along with the availability of cooperativity factors from radioligand displacement experiments are expected to improve the predictivity of in silico methodologies for allosteric drug discovery and boost the development of conformation-based pharmacological approaches. AVAILABILITY AND IMPLEMENTATION The GRALL library is distributed as a web-accessible database at the following link: https://ifm.chimie.unistra.fr/grall. For each molecular entry, it provides information on the chemical structure, the ligand-binding site, the direction of modulation, the potency, the 3D molecular structure and quantum-mechanical charges as determined by our in-house pipeline. CONTACT mcecchini@unistra.fr. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Adrien H Cerdan
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France
- Channel-Receptors Unit, Institut Pasteur, 75015 Paris, France
| | - Marion Sisquellas
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France
| | - Gilberto Pereira
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France
| | - Diego E Barreto Gomes
- Diretoria de Metrologia Aplicada às Ciências da Vida-Instituto Nacional de Metrologia, Qualidade e Tecnologia, Duque de Caxias 25.250-020, Brazil
| | - Jean-Pierre Changeux
- CNRS, URA 2182, F-75015, Collège de France, F-75005 Paris, France
- Kavli Institute for Brain & Mind, University of California San Diego, La Jolla, CA 92093, USA
| | - Marco Cecchini
- Institut de Chimie de Strasbourg, UMR7177, CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France
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18
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Changeux JP. Discovery of the First Neurotransmitter Receptor: The Acetylcholine Nicotinic Receptor. Biomolecules 2020; 10:E547. [PMID: 32260196 PMCID: PMC7226243 DOI: 10.3390/biom10040547] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/04/2020] [Accepted: 03/10/2020] [Indexed: 11/16/2022] Open
Abstract
The concept of pharmacological receptor was proposed at the turn of the 20th century but it took almost 70 years before the first receptor for a neurotransmitter was isolated and identified as a protein. This review retraces the history of the difficulties and successes in the identification of the nicotinic acetylcholine receptor, the first neurotransmitter receptor to be identified.
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Affiliation(s)
- Jean-Pierre Changeux
- Department of Neuroscience, CNRS UMR 3571, Institut Pasteur & Collège de France, 75015 Paris, France
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19
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Mashour GA, Roelfsema P, Changeux JP, Dehaene S. Conscious Processing and the Global Neuronal Workspace Hypothesis. Neuron 2020; 105:776-798. [PMID: 32135090 PMCID: PMC8770991 DOI: 10.1016/j.neuron.2020.01.026] [Citation(s) in RCA: 337] [Impact Index Per Article: 84.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/31/2019] [Accepted: 01/22/2020] [Indexed: 10/24/2022]
Abstract
We review the central tenets and neuroanatomical basis of the global neuronal workspace (GNW) hypothesis, which attempts to account for the main scientific observations regarding the elementary mechanisms of conscious processing in the human brain. The GNW hypothesis proposes that, in the conscious state, a non-linear network ignition associated with recurrent processing amplifies and sustains a neural representation, allowing the corresponding information to be globally accessed by local processors. We examine this hypothesis in light of recent data that contrast brain activity evoked by either conscious or non-conscious contents, as well as during conscious or non-conscious states, particularly general anesthesia. We also discuss the relationship between the intertwined concepts of conscious processing, attention, and working memory.
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Affiliation(s)
- George A Mashour
- Center for Consciousness Science, Neuroscience Graduate Program, and Department of Anesthesiology, University of Michigan, Ann Arbor, MI, USA
| | - Pieter Roelfsema
- Department of Vision & Cognition, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105 BA, Amsterdam, the Netherlands; Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, VU University, Amsterdam, the Netherlands; Department of Psychiatry, Academic Medical Center, Amsterdam, the Netherlands
| | - Jean-Pierre Changeux
- CNRS UMR 3571, Institut Pasteur, 75724 Paris, France; Collège de France, 11 Place Marcelin Berthelot, 75005 Paris, France; Kavli Institute for Brain & Mind, University of California, San Diego, La Jolla, CA, USA.
| | - Stanislas Dehaene
- Collège de France, 11 Place Marcelin Berthelot, 75005 Paris, France; Cognitive Neuroimaging Unit, CEA, INSERM, Université Paris-Sud, Université Paris-Saclay, NeuroSpin Center, 91191 Gif/Yvette, France.
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20
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Lou HC, Rømer Thomsen K, Changeux JP. The Molecular Organization of Self-awareness: Paralimbic Dopamine-GABA Interaction. Front Syst Neurosci 2020; 14:3. [PMID: 32047425 PMCID: PMC6997345 DOI: 10.3389/fnsys.2020.00003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 01/10/2020] [Indexed: 11/13/2022] Open
Abstract
The electrophysiology of the paralimbic network ("default mode") for self-awareness has drawn much attention in the past couple of decades. In contrast, knowledge of the molecular organization of conscious experience has only lately come into focus. We here review newer data on dopaminergic control of awareness in humans, particularly in self-awareness. These results implicate mainly dopaminergic neurotransmission and the control of GABAergic function directly in the paralimbic network. The findings are important for understanding addiction, developmental disorders, and dysfunctional consciousness.
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Affiliation(s)
- Hans C Lou
- Center of Functionally Integrative Neuroscience, Institute for Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Kristine Rømer Thomsen
- Department of Psychology and Behavioral Sciences, Center for Alcohol and Drug Research, School of Business and Social Sciences, Aarhus, Denmark
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Abstract
The concept of allosteric interaction was initially proposed to account for the inhibitory feedback mechanism mediated by bacterial regulatory enzymes. In contrast with the classical mechanism of competitive, steric, interaction between ligands for a common site, allosteric interactions take place between topographically distinct sites and are mediated by a discrete and reversible conformational change of the protein. The concept was soon extended to membrane receptors for neurotransmitters and shown to apply to the signal transduction process which, in the case of the acetylcholine nicotinic receptor (nAChR), links the ACh binding site to the ion channel. Pharmacological effectors, referred to as allosteric modulators, such as Ca2+ ions and ivermectin, were discovered that enhance the transduction process when they bind to sites distinct from the orthosteric ACh site and the ion channel. The recent X-ray and electron microscopy structures, at atomic resolution, of the resting and active conformations of several homologues of the nAChR, in combination with atomistic molecular dynamics simulations reveal a stepwise quaternary transition in the transduction process with tertiary changes modifying the boundaries between subunits. These interfaces host orthosteric and allosteric modulatory sites which structural organization changes in the course of the transition. The nAChR appears as a typical allosteric machine. The model emerging from these studies has led to the conception and development of several new pharmacological agents.This article is part of a discussion meeting issue 'Allostery and molecular machines'.
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Affiliation(s)
- Jean-Pierre Changeux
- CNRS UMR 3571, Institut Pasteur, Paris 75724, France .,Communications Cellulaires, Collège de France, Paris 75005, France
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22
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Changeux JP. Structural Identification of the Nicotinic Receptor Ion Channel. Trends Neurosci 2018; 41:67-70. [DOI: 10.1016/j.tins.2017.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 11/12/2017] [Indexed: 10/18/2022]
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Abstract
In the present paper, we suggest a potential new ethical analysis of addiction focusing on the relationship between aware and unaware processing in the brain. We take the case of the opioids epidemics to argue that a consideration of both aware and unaware processing provides a more comprehensive ethical framework to discuss the ethical issues raised by addiction. Finally, our hypothesis is that in addition to identified Central Nervous System's neuronal/neurochemical factors contributing to addictive dynamics, the socio-economic status plays a causal role through epigenetic processes, originating the need for additional reward in the brain. This provides a strong base for a socio-political form of responsibility for preventing and managing addiction crisis.
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Affiliation(s)
- Michele Farisco
- Centre for Research Ethics and Bioethics, Uppsala University, Uppsala, Sweden.,Science and Society Unit, Biogem, Biology and Molecular Genetics Institute, Ariano Irpino, Italy
| | - Kathinka Evers
- Centre for Research Ethics and Bioethics, Uppsala University, Uppsala, Sweden
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Abstract
Four major receptor families enable cells to respond to chemical and physical signals from their proximal environment. The ligand- and voltage-gated ion channels, G-protein-coupled receptors, nuclear hormone receptors and receptor tyrosine kinases are all allosteric proteins that carry multiple, spatially distinct, yet conformationally linked ligand-binding sites. Recent studies point to common mechanisms governing the allosteric transitions of these receptors, including the impact of oligomerization, pre-existing and functionally distinct conformational ensembles, intrinsically disordered regions, and the occurrence of allosteric modulatory sites. Importantly, synthetic allosteric modulators are being discovered for these receptors, providing an enriched, yet challenging, landscape for novel therapeutics.
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MESH Headings
- Allosteric Regulation/drug effects
- Allosteric Site/drug effects
- Animals
- Binding Sites/drug effects
- Dimerization
- Drug Discovery/trends
- Drugs, Investigational/chemistry
- Drugs, Investigational/pharmacology
- Humans
- Ligand-Gated Ion Channels/agonists
- Ligand-Gated Ion Channels/antagonists & inhibitors
- Ligand-Gated Ion Channels/chemistry
- Ligand-Gated Ion Channels/metabolism
- Ligands
- Models, Molecular
- Protein Conformation/drug effects
- Protein Multimerization/drug effects
- Receptor Protein-Tyrosine Kinases/agonists
- Receptor Protein-Tyrosine Kinases/antagonists & inhibitors
- Receptor Protein-Tyrosine Kinases/chemistry
- Receptor Protein-Tyrosine Kinases/metabolism
- Receptors, Cytoplasmic and Nuclear/agonists
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Receptors, Cytoplasmic and Nuclear/chemistry
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, G-Protein-Coupled/agonists
- Receptors, G-Protein-Coupled/antagonists & inhibitors
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/metabolism
- Voltage-Gated Sodium Channels/chemistry
- Voltage-Gated Sodium Channels/metabolism
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Affiliation(s)
| | - Arthur Christopoulos
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, VIC 3052 Parkville, Australia
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25
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Mathivanan S, Devesa I, Changeux JP, Ferrer-Montiel A. Bradykinin Induces TRPV1 Exocytotic Recruitment in Peptidergic Nociceptors. Front Pharmacol 2016; 7:178. [PMID: 27445816 PMCID: PMC4917537 DOI: 10.3389/fphar.2016.00178] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 06/06/2016] [Indexed: 01/09/2023] Open
Abstract
Transient receptor potential vanilloid I (TRPV1) sensitization in peripheral nociceptors is a prominent phenomenon that occurs in inflammatory pain conditions. Pro-algesic agents can potentiate TRPV1 activity in nociceptors through both stimulation of its channel gating and mobilization of channels to the neuronal surface in a context dependent manner. A recent study reported that ATP-induced TRPV1 sensitization in peptidergic nociceptors involves the exocytotic release of channels trafficked by large dense core vesicles (LDCVs) that cargo alpha-calcitonin gene related peptide alpha (αCGRP). We hypothesized that, similar to ATP, bradykinin may also use different mechanisms to sensitize TRPV1 channels in peptidergic and non-peptidergic nociceptors. We found that bradykinin notably enhances the excitability of peptidergic nociceptors, and sensitizes TRPV1, primarily through the bradykinin receptor 2 pathway. Notably, bradykinin sensitization of TRPV1 in peptidergic nociceptors was significantly blocked by inhibiting Ca2+-dependent neuronal exocytosis. In addition, silencing αCGRP gene expression, but not substance P, drastically reduced bradykinin-induced TRPV1 sensitization in peptidergic nociceptors. Taken together, these findings indicate that bradykinin-induced sensitization of TRPV1 in peptidergic nociceptors is partially mediated by the exocytotic mobilization of new channels trafficked by αCGRP-loaded LDCVs to the neuronal membrane. Our findings further imply a central role of αCGRP peptidergic nociceptors in peripheral algesic sensitization, and substantiate that inhibition of LDCVs exocytosis is a valuable therapeutic strategy to treat pain, as it concurrently reduces the release of pro-inflammatory peptides and the membrane recruitment of thermoTRP channels.
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Affiliation(s)
| | - Isabel Devesa
- Instituto de Biología Molecular y Celular, Universitas Miguel Hernández Elche, Spain
| | - Jean-Pierre Changeux
- College de FranceParis, France; Centre Nationale de la Recherche Scientifique, Institute Pasteur, Unité de Recherche AssociéeParis, France
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26
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Changeux JP, Carafoli E. Historical perspective: An INTERVIEW WITH JEAN-PIERRE CHANGEUX by Ernesto Carafoli. Biochem Biophys Res Commun 2015; 467:612-616. [PMID: 26467075 DOI: 10.1016/j.bbrc.2015.10.046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
| | - Ernesto Carafoli
- Venetian Institute of Molecular Medicine, Via G.Orus, 2, 35129, Padova, Italy.
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27
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Peschanski M, Bergeron M, Boué A, Coppens Y, Changeux JP, Corvol P, Lazar P, Kahn A, Bichet DG, Friedlander G, Epelbaum J, Kroemer G, Chneiweiss H, Munnich A, Bouvier M, Jordan B, Frydman R, Morange M, Fougereau M. [The 2000 years]. Med Sci (Paris) 2015; 31 Spec No 1:47-90. [PMID: 26038812 DOI: 10.1051/medsci/201531s1005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Wieskopf JS, Mathur J, Limapichat W, Post MR, Al-Qazzaz M, Sorge RE, Martin LJ, Zaykin DV, Smith SB, Freitas K, Austin JS, Dai F, Zhang J, Marcovitz J, Tuttle AH, Slepian PM, Clarke S, Drenan RM, Janes J, Al Sharari S, Segall SK, Aasvang EK, Lai W, Bittner R, Richards CI, Slade GD, Kehlet H, Walker J, Maskos U, Changeux JP, Devor M, Maixner W, Diatchenko L, Belfer I, Dougherty DA, Su AI, Lummis SCR, Imad Damaj M, Lester HA, Patapoutian A, Mogil JS. The nicotinic α6 subunit gene determines variability in chronic pain sensitivity via cross-inhibition of P2X2/3 receptors. Sci Transl Med 2015; 7:287ra72. [PMID: 25972004 PMCID: PMC5018401 DOI: 10.1126/scitranslmed.3009986] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Chronic pain is a highly prevalent and poorly managed human health problem. We used microarray-based expression genomics in 25 inbred mouse strains to identify dorsal root ganglion (DRG)-expressed genetic contributors to mechanical allodynia, a prominent symptom of chronic pain. We identified expression levels of Chrna6, which encodes the α6 subunit of the nicotinic acetylcholine receptor (nAChR), as highly associated with allodynia. We confirmed the importance of α6* (α6-containing) nAChRs by analyzing both gain- and loss-of-function mutants. We find that mechanical allodynia associated with neuropathic and inflammatory injuries is significantly altered in α6* mutants, and that α6* but not α4* nicotinic receptors are absolutely required for peripheral and/or spinal nicotine analgesia. Furthermore, we show that Chrna6's role in analgesia is at least partially due to direct interaction and cross-inhibition of α6* nAChRs with P2X2/3 receptors in DRG nociceptors. Finally, we establish the relevance of our results to humans by the observation of genetic association in patients suffering from chronic postsurgical and temporomandibular pain.
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Affiliation(s)
- Jeffrey S Wieskopf
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Jayanti Mathur
- Genomic Institute of the Novartis Research Foundation, San Diego, CA 92121, USA
| | - Walrati Limapichat
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Michael R Post
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Mona Al-Qazzaz
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Robert E Sorge
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Loren J Martin
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Dmitri V Zaykin
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA
| | - Shad B Smith
- Center for Neurosensory Disorders, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Kelen Freitas
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Jean-Sebastien Austin
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Feng Dai
- Departments of Anesthesiology and Human Genetics, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jie Zhang
- Genomic Institute of the Novartis Research Foundation, San Diego, CA 92121, USA
| | - Jaclyn Marcovitz
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Alexander H Tuttle
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Peter M Slepian
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Sarah Clarke
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada
| | - Ryan M Drenan
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
| | - Jeff Janes
- Genomic Institute of the Novartis Research Foundation, San Diego, CA 92121, USA
| | - Shakir Al Sharari
- Department of Pharmacology, King Saud University, P. O. Box 2457, Riyadh 11451, Saudi Arabia
| | - Samantha K Segall
- Center for Neurosensory Disorders, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Eske K Aasvang
- Section for Surgical Pathophysiology, Rigshospitalet, Copenhagen University, 2100 Copenhagen, Denmark
| | - Weike Lai
- Departments of Anesthesiology and Human Genetics, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Reinhard Bittner
- Department of Surgery, Marienhospital Stuttgart, 70199 Stuttgart, Germany
| | | | - Gary D Slade
- Department of Dental Ecology, School of Dentistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Henrik Kehlet
- Section for Surgical Pathophysiology, Rigshospitalet, Copenhagen University, 2100 Copenhagen, Denmark
| | - John Walker
- Genomic Institute of the Novartis Research Foundation, San Diego, CA 92121, USA
| | - Uwe Maskos
- Neurobiologie Intégrative des Systèmes Cholinergiques, CNRS UMR 3571, Département de Neuroscience, Institute Pasteur, 75724 Paris, France
| | - Jean-Pierre Changeux
- Neurobiologie Intégrative des Systèmes Cholinergiques, CNRS UMR 3571, Département de Neuroscience, Institute Pasteur, 75724 Paris, France
| | - Marshall Devor
- Department of Cell and Developmental Biology, Institute of Life Sciences and Center for Research on Pain, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - William Maixner
- Center for Neurosensory Disorders, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Luda Diatchenko
- Center for Neurosensory Disorders, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. Faculty of Dentistry, Department of Anesthesia, and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1G1, Canada
| | - Inna Belfer
- Departments of Anesthesiology and Human Genetics, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Dennis A Dougherty
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Andrew I Su
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Sarah C R Lummis
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - M Imad Damaj
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23219, USA
| | - Henry A Lester
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Ardem Patapoutian
- Department of Molecular and Cellular Neuroscience, The Scripps Research Institute, and Howard Hughes Medical Institute, La Jolla, CA 92037, USA
| | - Jeffrey S Mogil
- Department of Psychology and Alan Edwards Centre for Research on Pain, McGill University, Montreal, Quebec H3A 1B1, Canada.
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Sekiguchi H, Matsushita Y, Nishino Y, Ikezaki K, Miyazawa A, Yagi N, Huron C, Changeux JP, Corringer PJ, Sasaki YC. Single Molecule Motion Map of GLIC by Diffracted X-Ray Tracking. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.1059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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Cecchini M, Changeux JP. The nicotinic acetylcholine receptor and its prokaryotic homologues: Structure, conformational transitions & allosteric modulation. Neuropharmacology 2014; 96:137-49. [PMID: 25529272 DOI: 10.1016/j.neuropharm.2014.12.006] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 11/27/2014] [Accepted: 12/03/2014] [Indexed: 10/24/2022]
Abstract
Pentameric ligand-gated ion channels (pLGICs) play a central role in intercellular communications in the nervous system by converting the binding of a chemical messenger - a neurotransmitter - into an ion flux through the postsynaptic membrane. Here, we present an overview of the most recent advances on the signal transduction mechanism boosted by X-ray crystallography of both prokaryotic and eukaryotic homologues of the nicotinic acetylcholine receptor (nAChR) in conjunction with time-resolved analyses based on single-channel electrophysiology and Molecular Dynamics simulations. The available data consistently point to a global mechanism of gating that involves a large reorganization of the receptor mediated by two distinct quaternary transitions: a global twisting and a radial expansion/contraction of the extracellular domain. These transitions profoundly modify the organization of the interface between subunits, which host several sites for orthosteric and allosteric modulatory ligands. The same mechanism may thus mediate both positive and negative allosteric modulations of pLGICs ligand binding at topographically distinct sites. The emerging picture of signal transduction is expected to pave the way to new pharmacological strategies for the development of allosteric modulators of nAChR and pLGICs in general. This article is part of the Special Issue entitled 'The Nicotinic Acetylcholine Receptor: From Molecular Biology to Cognition'.
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Affiliation(s)
- Marco Cecchini
- ISIS, UMR 7006 CNRS, Université de Strasbourg, F-67083 Strasbourg Cedex, France.
| | - Jean-Pierre Changeux
- CNRS, URA 2182, F-75015 Paris, France; Collège de France, F-75005 Paris, France; Kavli Institute for Brain & Mind University of California, San Diego La Jolla, CA 92093, USA.
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32
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Abstract
The recent application of molecular dynamics (MD) methodology to investigate the allosteric transitions of the acetylcholine receptor and its prokaryotic and eukaryotic pentameric homologs has yielded new insights into the mechanisms of signal transduction by these receptors. Combined with available data on X-ray structures, MD techniques enable description of the dynamics of the conformational change at the atomic level, intra-molecular propagation of this signal transduction mechanism as a concerted stepwise process at physiological timescales and the control of this process by allosteric modulators, thereby offering new perspectives for drug design.
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Affiliation(s)
- Jean-Pierre Changeux
- UMR 3571 CNRS, Institut Pasteur, 25 rue du Docteur Roux, 75015 Paris, France
- Collège de France, 11 Place Marcelin Berthelot, 75005 Paris, France
- Kavli Brain-Mind Institute University of California, San Diego, CA USA
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33
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Christopoulos A, Changeux JP, Catterall WA, Fabbro D, Burris TP, Cidlowski JA, Olsen RW, Peters JA, Neubig RR, Pin JP, Sexton PM, Kenakin TP, Ehlert FJ, Spedding M, Langmead CJ. International Union of Basic and Clinical Pharmacology. XC. multisite pharmacology: recommendations for the nomenclature of receptor allosterism and allosteric ligands. Pharmacol Rev 2014; 66:918-47. [PMID: 25026896 PMCID: PMC11060431 DOI: 10.1124/pr.114.008862] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Allosteric interactions play vital roles in metabolic processes and signal transduction and, more recently, have become the focus of numerous pharmacological studies because of the potential for discovering more target-selective chemical probes and therapeutic agents. In addition to classic early studies on enzymes, there are now examples of small molecule allosteric modulators for all superfamilies of receptors encoded by the genome, including ligand- and voltage-gated ion channels, G protein-coupled receptors, nuclear hormone receptors, and receptor tyrosine kinases. As a consequence, a vast array of pharmacologic behaviors has been ascribed to allosteric ligands that can vary in a target-, ligand-, and cell-/tissue-dependent manner. The current article presents an overview of allostery as applied to receptor families and approaches for detecting and validating allosteric interactions and gives recommendations for the nomenclature of allosteric ligands and their properties.
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Affiliation(s)
- Arthur Christopoulos
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Jean-Pierre Changeux
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - William A Catterall
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Doriano Fabbro
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Thomas P Burris
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - John A Cidlowski
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Richard W Olsen
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - John A Peters
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Richard R Neubig
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Jean-Philippe Pin
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Patrick M Sexton
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Terry P Kenakin
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Frederick J Ehlert
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Michael Spedding
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
| | - Christopher J Langmead
- Drug Discovery Biology and Department of Pharmacology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia (A.C., P.M.S., C.J.L.); Collège de France and CNRS URA 2182, Institut Pasteur, Paris, France (J.-P.C.); Department of Pharmacology, School of Medicine, University of Washington, Seattle, Washington (W.A.C.); PIQUR Therapeutics AG, Basel, Switzerland (D.F.); Department of Pharmacological & Physiological Science, Saint Louis University School of Medicine, St. Louis, Louisiana (T.P.B.); Signal Transduction Laboratory, Molecular Endocrinology Group, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina (J.A.C.); Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California (R.W.O.); Division of Neuroscience, School of Medicine, University of Dundee, Scotland, United Kingdom (J.A.P.); Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan (R.R.N.); Institut de Genomique Fonctionelle, CNRS, Montpellier, France (J.-P.P.); Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina (T.P.K.); Department of Pharmacology, University of California, Irvine, California (F.J.E.); and Research Solutions SARL, Paris, France (M.S.)
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Abstract
A brief historical overview of the concept of allosteric interaction is presented together with the different kinds of allosteric control recognized, in the past decades, with the model system of pentameric ligandgated ion channels. Multiple levels of allosteric modulation are identified that include sites distributed in the extracellular ligand binding domain (e.g. Ca2+ or benzodiazepines), the transmembrane domain (e.g. general anesthetic and various allosteric modulators) and the cytoplasmic domain, as potential targets for drug design. The new opportunities offered by the recent technological developments are discussed.
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Taly A, Hénin J, Changeux JP, Cecchini M. Allosteric regulation of pentameric ligand-gated ion channels: an emerging mechanistic perspective. Channels (Austin) 2014; 8:350-60. [PMID: 25478624 PMCID: PMC4203737 DOI: 10.4161/chan.29444] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 06/03/2014] [Accepted: 06/03/2014] [Indexed: 12/22/2022] Open
Abstract
Pentameric ligand-gated ion channels (pLGICs) play a central role in intercellular communications in the nervous system by converting the binding of a chemical messenger—a neurotransmitter—into an ion flux through the postsynaptic membrane. They are oligomeric assemblies that provide prototypical examples of allosterically regulated integral membrane proteins. Here, we present an overview of the most recent advances on the signal transduction mechanism based on the X-ray structures of both prokaryotic and invertebrate eukaryotic pLGICs and atomistic Molecular Dynamics simulations. The present results suggest that ion gating involves a large structural reorganization of the molecule mediated by two distinct quaternary transitions, a global twisting and the blooming of the extracellular domain, which can be modulated by ligand binding at the topographically distinct orthosteric and allosteric sites. The emerging model of gating is consistent with a wealth of functional studies and will boost the development of novel pharmacological strategies.
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Affiliation(s)
- Antoine Taly
- Laboratoire de Biochimie Théorique; IBPC; CNRS and Université Paris Diderot; Paris, France
| | - Jérôme Hénin
- Laboratoire de Biochimie Théorique; IBPC; CNRS and Université Paris Diderot; Paris, France
| | - Jean-Pierre Changeux
- CNRS; URA 2182; F-75015 & Collège de France; Paris, France
- Kavli Institute for Brain & Mind University of California; San Diego La Jolla, CA USA
| | - Marco Cecchini
- ISIS; UMR 7006 CNRS; Université de Strasbourg; F-67083 Strasbourg Cedex, France
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36
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Abstract
Electrical excitation is interpreted in terms of a cooperative structural transition of membrane protomers coupled with the translocation of a permeant molecule in a non-equilibrium environment. Equations for flow of permeant and for membrane conformation are derived for the simple case of a single non-charged permeant. On the basis of a few simple physical assumptions, the theory predicts several important properties of electrically excitable membranes: the steepness of the relation between membrane conductance and potential, the presence of a negative conductance, and the occurrence of instabilities following rapid perturbations of membrane environment, giving rise to some simple cases of action potentials. Several experimental tests of the membrane with its changes of electrical properties are proposed. From a thermodynamic point of view, an electrically excitable membrane, in its resting state, lies beyond a dissipative instability and consequently is in a non-equilibrium state but with stable organization, a "dissipative structure" of Prigogine. Membrane excitation following a small perturbation of the environment would correspond to a jump from such an organization to another stable organization but close to thermodynamic equilibrium. It is shown how the cooperative molecular properties of the membrane are amplified by energy dissipation at the macroscopic level.
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Affiliation(s)
- R Blumenthal
- Département de Biologie Moléculaire, Institut Pasteur, Paris, France
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37
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38
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Abstract
Throughout this Reflections article, I have tried to follow up on the genesis in the 1960s and subsequent evolution of the concept of allosteric interaction and to examine its consequences within the past decades, essentially in the field of the neuroscience. The main conclusion is that allosteric mechanisms built on similar structural principles operate in bacterial regulatory enzymes, gene repressors (and the related nuclear receptors), rhodopsin, G-protein-coupled receptors, neurotransmitter receptors, ion channels, and so on from prokaryotes up to the human brain yet with important features of their own. Thus, future research on these basic cybernetic sensors is expected to develop in two major directions: at the elementary level, toward the atomic structure and molecular dynamics of the conformational changes involved in signal recognition and transduction, but also at a higher level of organization, the contribution of allosteric mechanisms to the modulation of brain functions.
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Affiliation(s)
- Jean-Pierre Changeux
- Collège de France, 75005 Paris and the Institut Pasteur, 75724 Paris Cedex 15, France.
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Changeux JP. The Origins of Allostery: From Personal Memories to Material for the Future. J Mol Biol 2013; 425:1396-406. [DOI: 10.1016/j.jmb.2013.02.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 02/20/2013] [Indexed: 11/16/2022]
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Changeux JP. De la molécule au langage : La biologie du cerveau en plein essor. Med Sci (Paris) 2013. [DOI: 10.4267/10608/3865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Corringer PJ, Poitevin F, Prevost MS, Sauguet L, Delarue M, Changeux JP. Structure and pharmacology of pentameric receptor channels: from bacteria to brain. Structure 2012; 20:941-56. [PMID: 22681900 DOI: 10.1016/j.str.2012.05.003] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 05/16/2012] [Accepted: 05/17/2012] [Indexed: 01/21/2023]
Abstract
Orthologs of the pentameric receptor channels that mediate fast synaptic transmission in the central and peripheral nervous systems have been found in several bacterial species and in a single archaea genus. Recent X-ray structures of bacterial and invertebrate pentameric receptors point to a striking conservation of the structural features within the whole family, even between distant prokaryotic and eukaryotic members. These structural data reveal general principles of molecular organization that allow allosteric membrane proteins to mediate chemoelectric transduction. Notably, several conformations have been solved, including open and closed channels with distinct global tertiary and quaternary structure. The data reveal features of the ion channel architecture and of diverse categories of binding sites, such as those that bind orthosteric ligands, including neurotransmitters, and those that bind allosteric modulators, such as general anesthetics, ivermectin, or lipids. In this review, we summarize the most recent data, discuss insights into the mechanism of action in these systems, and elaborate on newly opened avenues for drug design.
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Abstract
A critical event in the history of biological chemistry was the chemical identification of the first neurotransmitter receptor, the nicotinic acetylcholine receptor. Disciplines as diverse as electrophysiology, pharmacology, and biochemistry joined together in a unified and rational manner with the common goal of successfully identifying the molecular device that converts a chemical signal into an electrical one in the nervous system. The nicotinic receptor has become the founding father of a broad family of pentameric membrane receptors, paving the way for their identification, including that of the GABA(A) receptors.
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Lykhmus O, Koval L, Skok M, Zouridakis M, Zisimopoulou P, Tzartos S, Tsetlin V, Granon S, Changeux JP, Komisarenko S, Cloëz-Tayarani I. Antibodies against extracellular domains of α4 and α7 subunits alter the levels of nicotinic receptors in the mouse brain and affect memory: possible relevance to Alzheimer's pathology. J Alzheimers Dis 2012; 24:693-704. [PMID: 21321393 DOI: 10.3233/jad-2011-101842] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) of α4β2 and α7 subtypes expressed in the brain neurons are involved in regulating memory and cognition. Their level is decreased upon several neurodegenerative disorders including Alzheimer's disease (AD), although the reasons for such a decrease are not completely understood. To test whether the nAChR-specific antibodies can affect the brain nAChRs and influence the behavior, we either immunized mice with recombinant extracellular domains of α4 and α7, subunits α4(1-209) and α7(1-208), or injected them with α7(1-208)-specific antibodies. A decrease of α4β2- and α7-nAChRs accompanied with an increase of α4β4-nAChRs in brain membranes of immunized mice was observed. Both α4(1-209)- and α7(1-208)-specific antibodies were detected in the brain membrane lysates of immunized mice. Antibody injection resulted in brain nAChR decrease only if mice were co-injected intraperitoneally with bacterial lipopolysaccharide. Brain sections of immunized mice were analyzed for the binding of [125I]-α-bungarotoxin and [125I]-epibatidine. A decrease in α-bungarotoxin binding in striatum (nucleus accumbens and caudate putamen) accompanied with an increase of epibatidine binding in the forebrain and caudate putamen was observed in mice immunized with either α4 or α7 nAChR domains compared to those immunized with BSA. Mice immunized with α7(1-208) demonstrated significantly worse episodic memory measured in a novel object recognition task compared to non-immunized animals but did not differ from the controls in locomotor or anxiety-related tests. These results suggest that nAChR-specific antibodies are able to penetrate the brain upon inflammation with resulting decreases of brain nAChRs and worsening episodic memory.
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Abstract
Nicotinic and serotoninergic 5HT3 receptors share important sequence identities except for their cytoplasmic loop. Both ends of this loop display conserved 3D helical structures with distinct primary sequences. We decided to check whether these two helices named F and G play a role in the sub-cellular distribution of different nicotinic receptors. We systematically exchanged each helix with the equivalent sequence of neuronal nicotinic and alpha4, beta2 and alpha7 subunits in the functional chimeric alpha7-5HT3 receptor used as a model system. The new chimeras were expressed in vitro in polarized epithelial cells from pig kidney. We quantified synthesis and export of the receptors to the cell surface by measuring alpha-bungarotoxin binding sites. Immunogold labelling was used, at the electron microscope level, to determine the amount of each chimera present at either domain, apical and/or basolateral, of these cells. We noticed that in epithelial cells the majority of alpha-bungarotoxin binding sites remained sequestered in the cytoplasm as already observed in neurons in vivo. The majority of the pentamers present at the cell surface were located at the apical domain. Our results suggest that helix F and G differently regulate assembly and export to the cell surface of alpha-bungarotoxin binding receptors.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/metabolism
- Binding Sites
- Bungarotoxins/metabolism
- Cell Polarity
- Cells, Cultured
- Cytoplasm/metabolism
- Epithelial Cells/ultrastructure
- Green Fluorescent Proteins
- Hippocampus/cytology
- Hippocampus/embryology
- LLC-PK1 Cells
- Luminescent Proteins/metabolism
- Neurons/cytology
- Neurons/metabolism
- Protein Structure, Quaternary
- Protein Structure, Secondary
- Rats
- Rats, Sprague-Dawley
- Receptors, Nicotinic/chemistry
- Receptors, Nicotinic/genetics
- Receptors, Nicotinic/metabolism
- Receptors, Serotonin/chemistry
- Receptors, Serotonin/genetics
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
- Sequence Homology, Amino Acid
- Swine
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Affiliation(s)
- A Devillers-Thiéry
- Laboratoire Récepteurs et Cognition, Département des neuroscience, Institut Pasteur, 25 rue du Dr. Roux, 75724 Paris 15, France
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Abstract
The Monod-Wyman-Changeux (MWC) model was conceived in 1965 to account for the signal transduction and cooperative properties of bacterial regulatory enzymes and hemoglobin. It was soon extended to pharmacological receptors for neurotransmitters and other macromolecular entities involved in intracellular and intercellular communications. Five decades later, the two main hypotheses of the model are reexamined on the basis of a variety of regulatory proteins with known X-ray structures: (a) Regulatory proteins possess an oligomeric structure with symmetry properties, and (b) the allosteric interactions between topographically distinct sites are mediated by a conformational transition established between a few preestablished states with conservation of symmetry and ligand-directed conformational selection. Several well-documented examples are adequately represented by the MWC model, yet a few possible exceptions are noted. New questions are raised concerning the dynamics of the allosteric transitions and more complex supramolecular ensembles.
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Affiliation(s)
- Jean-Pierre Changeux
- Collège de France & Institut Pasteur, URA CNRS 2182, Paris Cedex 15 75724, France.
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Corringer PJ, Nury H, Van Renterghem C, Yeng Y, Tran A, Baaden M, Changeux JP, Sonner JM, Delarue M. Allosteric Transition and Pharmacological Modulation of Pentameric Channel-Receptors: The Case of General Anesthetics. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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Nury H, Van Renterghem C, Weng Y, Tran A, Baaden M, Dufresne V, Changeux JP, Sonner J, Delarue M, Corringer PJ. X-Ray Structures of General Anaesthetics Bound to a Pentameric Ligand-Gated Ion Channel. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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Granon S, Changeux JP. Deciding between conflicting motivations: what mice make of their prefrontal cortex. Behav Brain Res 2011; 229:419-26. [PMID: 22108342 DOI: 10.1016/j.bbr.2011.11.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Revised: 11/03/2011] [Accepted: 11/07/2011] [Indexed: 10/15/2022]
Abstract
We investigated the contribution of the mouse prefrontal cortex and, more specifically, the prelimbic area, to a learning task that highlights a choice between two conflicting motivations, the one for food seeking and the one for novelty exploration. We used a learning paradigm in a cross maze task that targets first motivation conflict and second flexible rule adaptation following environmental changes. We show that mice with prelimbic lesions, which showed normal spatial learning, exhibit impairment in switching from one type of reward - food retrieval - to another type - novelty exploration - and sustained difficulties in adapting their behaviour when the rule is changing repeatedly. Mice, like other mammals, possess a prefrontal cortex that participates in the control of the flexible switch between concurrent natural motivations and in the rapid and flexible adaptation to external changes. These results open a way to study in mice models motivation conflict and cognitive adaptation, brain functions known to be compromised in several psychiatric conditions in humans in which the prefrontal cortex functioning is altered.
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Affiliation(s)
- Sylvie Granon
- Centre de Neuroscience Paris Sud, Université Paris Sud 11, CNRS 8195, Orsay, France.
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Abstract
We here review experimental findings relevant for the pharmacology of conscious experience, an issue largely neglected in pharmacological research. First, we focus on self-awareness, a pivotal component of conscious experience and its integration within the global neuronal network (GNW), a theoretical concept that unifies convergent approaches on the neural bases of conscious processing. We report recent evidence to show that self-awareness mobilizes a paralimbic circuitry of γ synchrony, and that such synchrony is, in particular, regulated by GABA interneurons under the control of acetylcholine and dopamine. Recent data illustrate that these neurotransmitters establish a causal relationship with the control of self-awareness. The hypothesis is presented that not only is self-awareness chemically regulated, but the reverse may be true. Long-term deficit in self-control of drug intake would result in compulsive substance use, accompanied, in particular, with lesions of the paralimbic circuitry of self-awareness, leading to aggravation of substance abuse, resulting in addiction in a vicious circle. Finally, we propose that the emergent pharmacology of conscious experience may provide new perspectives, not only in substance addiction but also in the many other pathological conditions with deficient self-awareness.
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