1
|
Kodirov SA. Adam, amigo, brain, and K channel. Biophys Rev 2023; 15:1393-1424. [PMID: 37975011 PMCID: PMC10643815 DOI: 10.1007/s12551-023-01163-5] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 09/28/2023] [Indexed: 11/19/2023] Open
Abstract
Voltage-dependent K+ (Kv) channels are diverse, comprising the classical Shab - Kv2, Shaker - Kv1, Shal - Kv4, and Shaw - Kv3 families. The Shaker family alone consists of Kv1.1, Kv1.2, Kv1.3, Kv1.4, Kv1.5, Kv1.6, and Kv1.7. Moreover, the Shab family comprises two functional (Kv2.1 and Kv2.2) and several "silent" alpha subunits (Kv2.3, Kv5, Kv6, Kv8, and Kv9), which do not generate K current. However, e.g., Kv8.1, via heteromerization, inhibits outward currents of the same family or even that of Shaw. This property of Kv8.1 is similar to those of designated beta subunits or non-selective auxiliary elements, including ADAM or AMIGO proteins. Kv channels and, in turn, ADAM may modulate the synaptic long-term potentiation (LTP). Prevailingly, Kv1.1 and Kv1.5 are attributed to respective brain and heart pathologies, some of which may occur simultaneously. The aforementioned channel proteins are apparently involved in several brain pathologies, including schizophrenia and seizures.
Collapse
Affiliation(s)
- Sodikdjon A. Kodirov
- Department of Biological Sciences, University of Texas at Brownsville, Brownsville, TX 78520 USA
- Pavlov Institute of Physiology, Russian Academy of Sciences, Saint Petersburg, Russia
- Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisbon, Portugal
- Almazov Federal Heart, Blood and Endocrinology Centre, Saint Petersburg, 197341 Russia
- Institute for Physiology and Pathophysiology, Johannes Kepler University, Linz, Austria
| |
Collapse
|
2
|
Cheng F, Dennis AB, Osuoha JI, Canitz J, Kirschbaum F, Tiedemann R. A new genome assembly of an African weakly electric fish (Campylomormyrus compressirostris, Mormyridae) indicates rapid gene family evolution in Osteoglossomorpha. BMC Genomics 2023; 24:129. [PMID: 36941548 PMCID: PMC10029256 DOI: 10.1186/s12864-023-09196-6] [Citation(s) in RCA: 1] [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: 11/16/2022] [Accepted: 02/20/2023] [Indexed: 03/23/2023] Open
Abstract
BACKGROUND Teleost fishes comprise more than half of the vertebrate species. Within teleosts, most phylogenies consider the split between Osteoglossomorpha and Euteleosteomorpha/Otomorpha as basal, preceded only by the derivation of the most primitive group of teleosts, the Elopomorpha. While Osteoglossomorpha are generally species poor, the taxon contains the African weakly electric fish (Mormyroidei), which have radiated into numerous species. Within the mormyrids, the genus Campylomormyrus is mostly endemic to the Congo Basin. Campylomormyrus serves as a model to understand mechanisms of adaptive radiation and ecological speciation, especially with regard to its highly diverse species-specific electric organ discharges (EOD). Currently, there are few well-annotated genomes available for electric fish in general and mormyrids in particular. Our study aims at producing a high-quality genome assembly and to use this to examine genome evolution in relation to other teleosts. This will facilitate further understanding of the evolution of the osteoglossomorpha fish in general and of electric fish in particular. RESULTS A high-quality weakly electric fish (C. compressirostris) genome was produced from a single individual with a genome size of 862 Mb, consisting of 1,497 contigs with an N50 of 1,399 kb and a GC-content of 43.69%. Gene predictions identified 34,492 protein-coding genes, which is a higher number than in the two other available Osteoglossomorpha genomes of Paramormyrops kingsleyae and Scleropages formosus. A Computational Analysis of gene Family Evolution (CAFE5) comparing 33 teleost fish genomes suggests an overall faster gene family turnover rate in Osteoglossomorpha than in Otomorpha and Euteleosteomorpha. Moreover, the ratios of expanded/contracted gene family numbers in Osteoglossomorpha are significantly higher than in the other two taxa, except for species that had undergone an additional genome duplication (Cyprinus carpio and Oncorhynchus mykiss). As potassium channel proteins are hypothesized to play a key role in EOD diversity among species, we put a special focus on them, and manually curated 16 Kv1 genes. We identified a tandem duplication in the KCNA7a gene in the genome of C. compressirostris. CONCLUSIONS We present the fourth genome of an electric fish and the third well-annotated genome for Osteoglossomorpha, enabling us to compare gene family evolution among major teleost lineages. Osteoglossomorpha appear to exhibit rapid gene family evolution, with more gene family expansions than contractions. The curated Kv1 gene family showed seven gene clusters, which is more than in other analyzed fish genomes outside Osteoglossomorpha. The KCNA7a, encoding for a potassium channel central for EOD production and modulation, is tandemly duplicated which may related to the diverse EOD observed among Campylomormyrus species.
Collapse
Affiliation(s)
- Feng Cheng
- Unit of Evolutionary Biology and Systematic Zoology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Alice B Dennis
- Unit of Evolutionary Biology and Systematic Zoology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
- Laboratory of Adaptive Evolution and Genomics, Research Unit of Environmental and Evolutionary Biology, Institute of Life, Earth & Environnment, University of Namur, Namur, Belgium
| | - Josephine Ijeoma Osuoha
- Unit of Evolutionary Biology and Systematic Zoology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
| | - Julia Canitz
- Senckenberg German Entomological Institute, Müncheberg, Germany
| | - Frank Kirschbaum
- Unit of Evolutionary Biology and Systematic Zoology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany
- Department of Crop and Animal Science, Faculty of Life Sciences, Humboldt University, Berlin, Germany
| | - Ralph Tiedemann
- Unit of Evolutionary Biology and Systematic Zoology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany.
| |
Collapse
|
3
|
Wang ZW, Trussell LO, Vedantham K. Regulation of Neurotransmitter Release by K + Channels. Adv Neurobiol 2023; 33:305-331. [PMID: 37615872 DOI: 10.1007/978-3-031-34229-5_12] [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] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
K+ channels play potent roles in the process of neurotransmitter release by influencing the action potential waveform and modulating neuronal excitability and release probability. These diverse effects of K+ channel activation are ensured by the wide variety of K+ channel genes and their differential expression in different cell types. Accordingly, a variety of K+ channels have been implicated in regulating neurotransmitter release, including the Ca2+- and voltage-gated K+ channel Slo1 (also known as BK channel), voltage-gated K+ channels of the Kv3 (Shaw-type), Kv1 (Shaker-type), and Kv7 (KCNQ) families, G-protein-gated inwardly rectifying K+ (GIRK) channels, and SLO-2 (a Ca2+-. Cl-, and voltage-gated K+ channel in C. elegans). These channels vary in their expression patterns, subcellular localization, and biophysical properties. Their roles in neurotransmitter release may also vary depending on the synapse and physiological or experimental conditions. This chapter summarizes key findings about the roles of K+ channels in regulating neurotransmitter release.
Collapse
Affiliation(s)
- Zhao-Wen Wang
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, USA.
| | - Laurence O Trussell
- Oregon Hearing Research Center & Vollum Institute, Oregon Health and Science University, Portland, OR, USA
| | - Kiranmayi Vedantham
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, USA
| |
Collapse
|
4
|
Abstract
The functioning of voltage-dependent K channels (Kv) may correlate with the physiological state of brain in organisms, including the sleep in Drosophila. Apparently, all major types of K currents are expressed in CNS of this model organism. These are the Shab-Kv2, Shaker-Kv1, Shal-Kv4, and Shaw-Kv3 α subunits and can be deciphered by patch-clamp technique. Although it is plausible that some of these channels may play a prevailing role in sleep or wakefulness, several of recent data are not conclusive. It needs to be defined that indeed the frequency of action potentials in large ventral lateral pacemaker neurons is either higher or lower during the morning or night because of an increased Kv3 and Kv4 currents, respectively. The outcomes of dynamic-clamp approach in combination with electrophysiology in insects are unreliable in contrast to those in mammalian neurons. Since the addition of virtual Kv conductance during any Zeitgeber time should not significantly alter the resting membrane potential. This review explains the Drosophila sleep behavior based on neural activity with respect to K current-driven action potential rate.
Collapse
Affiliation(s)
- Sodikdjon A. Kodirov
- Pavlov Institute of Physiology, Russian Academy of Sciences, Saint Petersburg, Russia
- Instituto de Medicina Molecular, Universidade de Lisboa, Lisbon, Portugal
- Department of Biological Sciences, University of Texas at Brownsville, Brownsville, Texas, USA
| |
Collapse
|
5
|
Baudin P, Cousyn L, Navarro V. The LGI1 protein: molecular structure, physiological functions and disruption-related seizures. Cell Mol Life Sci 2021; 79:16. [PMID: 34967933 DOI: 10.1007/s00018-021-04088-y] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 01/16/2023]
Abstract
Leucine-rich, glioma inactivated 1 (LGI1) is a secreted glycoprotein, mainly expressed in the brain, and involved in central nervous system development and physiology. Mutations of LGI1 have been linked to autosomal dominant lateral temporal lobe epilepsy (ADLTE). Recently auto-antibodies against LGI1 have been described as the basis for an autoimmune encephalitis, associated with specific motor and limbic epileptic seizures. It is the second most common cause of autoimmune encephalitis. This review presents details on the molecular structure, expression and physiological functions of LGI1, and examines how their disruption underlies human pathologies. Knock-down of LGI1 in rodents reveals that this protein is necessary for normal brain development. In mature brains, LGI1 is associated with Kv1 channels and AMPA receptors, via domain-specific interaction with membrane anchoring proteins and contributes to regulation of the expression and function of these channels. Loss of function, due to mutations or autoantibodies, of this key protein in the control of neuronal activity is a common feature in the genesis of epileptic seizures in ADLTE and anti-LGI1 autoimmune encephalitis.
Collapse
Affiliation(s)
- Paul Baudin
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
| | - Louis Cousyn
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France.,AP-HP, Epilepsy Unit, Pitié-Salpêtrière Hospital, DMU Neurosciences, Paris, France
| | - Vincent Navarro
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France. .,AP-HP, Epilepsy Unit, Pitié-Salpêtrière Hospital, DMU Neurosciences, Paris, France. .,AP-HP, Center of Reference for Rare Epilepsies, Pitié-Salpêtrière Hospital, 47-83 Boulevard de l'Hôpital, 75013, Paris, France.
| |
Collapse
|
6
|
Finol-Urdaneta RK, Belovanovic A, Micic-Vicovac M, Kinsella GK, McArthur JR, Al-Sabi A. Marine Toxins Targeting Kv1 Channels: Pharmacological Tools and Therapeutic Scaffolds. Mar Drugs 2020; 18:E173. [PMID: 32245015 PMCID: PMC7143316 DOI: 10.3390/md18030173] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [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: 02/03/2020] [Revised: 03/15/2020] [Accepted: 03/16/2020] [Indexed: 12/11/2022] Open
Abstract
Toxins from marine animals provide molecular tools for the study of many ion channels, including mammalian voltage-gated potassium channels of the Kv1 family. Selectivity profiling and molecular investigation of these toxins have contributed to the development of novel drug leads with therapeutic potential for the treatment of ion channel-related diseases or channelopathies. Here, we review specific peptide and small-molecule marine toxins modulating Kv1 channels and thus cover recent findings of bioactives found in the venoms of marine Gastropod (cone snails), Cnidarian (sea anemones), and small compounds from cyanobacteria. Furthermore, we discuss pivotal advancements at exploiting the interaction of κM-conotoxin RIIIJ and heteromeric Kv1.1/1.2 channels as prevalent neuronal Kv complex. RIIIJ's exquisite Kv1 subtype selectivity underpins a novel and facile functional classification of large-diameter dorsal root ganglion neurons. The vast potential of marine toxins warrants further collaborative efforts and high-throughput approaches aimed at the discovery and profiling of Kv1-targeted bioactives, which will greatly accelerate the development of a thorough molecular toolbox and much-needed therapeutics.
Collapse
Affiliation(s)
- Rocio K. Finol-Urdaneta
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW 2522, Australia;
- Electrophysiology Facility for Cell Phenotyping and Drug Discovery, Wollongong, NSW 2522, Australia
| | - Aleksandra Belovanovic
- College of Engineering and Technology, American University of the Middle East, Kuwait; (A.B.); (M.M.-V.)
| | - Milica Micic-Vicovac
- College of Engineering and Technology, American University of the Middle East, Kuwait; (A.B.); (M.M.-V.)
| | - Gemma K. Kinsella
- School of Food Science and Environmental Health, College of Sciences and Health, Technological University Dublin, D07 ADY7 Dublin, Ireland;
| | - Jeffrey R. McArthur
- Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, NSW 2522, Australia;
| | - Ahmed Al-Sabi
- College of Engineering and Technology, American University of the Middle East, Kuwait; (A.B.); (M.M.-V.)
| |
Collapse
|
7
|
Abstract
The largest biomass of channel proteins is located in unicellular organisms and bacteria that have no organs. However, orchestrated bidirectional ionic currents across the cell membrane via the channels are important for the functioning of organs of organisms, and equally concern both fauna or flora. Several ion channels are activated in the course of action potentials. One of the hallmarks of voltage-dependent channels is a 'tail current' - deactivation as observed after prior and sufficient activation predominantly at more depolarized potentials e.g. for Kv while upon hyperpolarization for HCN α subunits. Tail current also reflects the timing of channel closure that is initiated upon termination of stimuli. Finally, deactivation of currents during repolarization could be a selective estimate for given channel as in case of HERG, if dedicated long and more depolarized 'tail pulse' is used. Since from a holding potential of e.g. -70 mV are often a family of outward K+ currents comprising IA and IK are simultaneously activated in native cells.
Collapse
Affiliation(s)
- Sodikdjon A Kodirov
- Pavlov Institute of Physiology, Russian Academy of Sciences, Saint Petersburg, Russia; Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA; Almazov Federal Heart, Blood and Endocrinology Centre, Saint Petersburg, 197341, Russia; Institute of Experimental Medicine, I. P. Pavlov Department of Physiology, Russian Academy of Medical Sciences, Saint Petersburg, Russia; Laboratory of Emotions' Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093, Poland.
| |
Collapse
|
8
|
Saint-Martin M, Pieters A, Déchelotte B, Malleval C, Pinatel D, Pascual O, Karagogeos D, Honnorat J, Pellier-Monnin V, Noraz N. Impact of anti-CASPR2 autoantibodies from patients with autoimmune encephalitis on CASPR2/TAG-1 interaction and Kv1 expression. J Autoimmun 2019; 103:102284. [PMID: 31176559 DOI: 10.1016/j.jaut.2019.05.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [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: 02/13/2019] [Revised: 05/08/2019] [Accepted: 05/14/2019] [Indexed: 12/19/2022]
Abstract
Autoantibodies against CASPR2 (contactin-associated protein-like 2) have been linked to autoimmune limbic encephalitis that manifests with memory disorders and temporal lobe seizures. According to the growing number of data supporting a role for CASPR2 in neuronal excitability, CASPR2 forms a molecular complex with transient axonal glycoprotein-1 (TAG-1) and shaker-type voltage-gated potassium channels (Kv1.1 and Kv1.2) in compartments critical for neuronal activity and is required for Kv1 proper positioning. Whereas the perturbation of these functions could explain the symptoms observed in patients, the pathogenic role of anti-CASPR2 antibodies has been poorly studied. In the present study, we find that patient autoantibodies alter Caspr2 distribution at the cell membrane promoting cluster formation. We confirm in a HEK cellular model that the anti-CASPR2 antibodies impede CASPR2/TAG-1 interaction and we identify the domains of CASPR2 and TAG-1 taking part in this interaction. Moreover, introduction of CASPR2 into HEK cells induces a marked increase of the level of Kv1.2 surface expression and in cultures of hippocampal neurons Caspr2-positive inhibitory neurons appear to specifically express high levels of Kv1.2. Importantly, in both cellular models, anti-CASPR2 patient autoAb increase Kv1.2 expression. These results provide new insights into the pathogenic role of autoAb in the disease.
Collapse
Affiliation(s)
- Margaux Saint-Martin
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Alanah Pieters
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Benoît Déchelotte
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Céline Malleval
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Delphine Pinatel
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Olivier Pascual
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Domna Karagogeos
- University of Crete Medical School and IMBB-FORTH, Heraklion, Crete GR, 70013, Greece
| | - Jérôme Honnorat
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France; Hospices Civils de Lyon, Lyon, F-69000, France
| | - Véronique Pellier-Monnin
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France
| | - Nelly Noraz
- INSERM U1217, Institut NeuroMyoGène, Lyon, F-69000, France; CNRS UMR5310, Institut NeuroMyoGène, Lyon, F-69000, France; University Claude Bernard Lyon 1, Lyon, F-69000, France.
| |
Collapse
|
9
|
Saint-Martin M, Joubert B, Pellier-Monnin V, Pascual O, Noraz N, Honnorat J. Contactin-associated protein-like 2, a protein of the neurexin family involved in several human diseases. Eur J Neurosci 2018; 48:1906-1923. [PMID: 30028556 DOI: 10.1111/ejn.14081] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [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: 03/28/2018] [Revised: 06/08/2018] [Accepted: 07/02/2018] [Indexed: 12/11/2022]
Abstract
Contactin-associated protein-like 2 (CASPR2) is a cell adhesion protein of the neurexin family. Proteins of this family have been shown to play a role in the development of the nervous system, in synaptic functions, and in neurological diseases. Over recent years, CASPR2 function has gained an increasing interest as demonstrated by the growing number of publications. Here, we gather published data to comprehensively review CASPR2 functions within the nervous system in relation to CASPR2-related diseases in humans. On the one hand, studies on Cntnap2 (coding for CASPR2) knockout mice revealed its role during development, especially, in setting-up the inhibitory network. Consistent with this result, mutations in the CNTNAP2 gene coding for CASPR2 in human have been identified in neurodevelopmental disorders such as autism, intellectual disability, and epilepsy. On the other hand, CASPR2 was shown to play a role beyond development, in the localization of voltage-gated potassium channel (VGKC) complex that is composed of TAG-1, Kv1.1, and Kv1.2. This complex was found in several subcellular compartments essential for action potential propagation: the node of Ranvier, the axon initial segment, and the synapse. In line with a role of CASPR2 in the mature nervous system, neurological autoimmune diseases have been described in patients without neurodevelopmental disorders but with antibodies directed against CASPR2. These autoimmune diseases were of two types: central with memory disorders and temporal lobe seizures, or peripheral with muscular hyperactivity. Overall, we review the up-to-date knowledge on CASPR2 function and pinpoint confused or lacking information that will need further investigation.
Collapse
Affiliation(s)
- Margaux Saint-Martin
- Institut NeuroMyoGene INSERM U1217/CNRS UMR 5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Bastien Joubert
- Institut NeuroMyoGene INSERM U1217/CNRS UMR 5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France.,French Reference Center on Paraneoplastic Neurological Syndrome, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France
| | - Véronique Pellier-Monnin
- Institut NeuroMyoGene INSERM U1217/CNRS UMR 5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Olivier Pascual
- Institut NeuroMyoGene INSERM U1217/CNRS UMR 5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Nelly Noraz
- Institut NeuroMyoGene INSERM U1217/CNRS UMR 5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Jérôme Honnorat
- Institut NeuroMyoGene INSERM U1217/CNRS UMR 5310, Université de Lyon, Université Claude Bernard Lyon 1, Lyon, France.,French Reference Center on Paraneoplastic Neurological Syndrome, Hospices Civils de Lyon, Hôpital Neurologique, Bron, France
| |
Collapse
|
10
|
Dawes JM, Weir GA, Middleton SJ, Patel R, Chisholm KI, Pettingill P, Peck LJ, Sheridan J, Shakir A, Jacobson L, Gutierrez-Mecinas M, Galino J, Walcher J, Kühnemund J, Kuehn H, Sanna MD, Lang B, Clark AJ, Themistocleous AC, Iwagaki N, West SJ, Werynska K, Carroll L, Trendafilova T, Menassa DA, Giannoccaro MP, Coutinho E, Cervellini I, Tewari D, Buckley C, Leite MI, Wildner H, Zeilhofer HU, Peles E, Todd AJ, McMahon SB, Dickenson AH, Lewin GR, Vincent A, Bennett DL. Immune or Genetic-Mediated Disruption of CASPR2 Causes Pain Hypersensitivity Due to Enhanced Primary Afferent Excitability. Neuron 2018; 97:806-822.e10. [PMID: 29429934 DOI: 10.1016/j.neuron.2018.01.033] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 12/04/2017] [Accepted: 01/12/2018] [Indexed: 11/22/2022]
Abstract
Human autoantibodies to contactin-associated protein-like 2 (CASPR2) are often associated with neuropathic pain, and CASPR2 mutations have been linked to autism spectrum disorders, in which sensory dysfunction is increasingly recognized. Human CASPR2 autoantibodies, when injected into mice, were peripherally restricted and resulted in mechanical pain-related hypersensitivity in the absence of neural injury. We therefore investigated the mechanism by which CASPR2 modulates nociceptive function. Mice lacking CASPR2 (Cntnap2−/−) demonstrated enhanced pain-related hypersensitivity to noxious mechanical stimuli, heat, and algogens. Both primary afferent excitability and subsequent nociceptive transmission within the dorsal horn were increased in Cntnap2−/− mice. Either immune or genetic-mediated ablation of CASPR2 enhanced the excitability of DRG neurons in a cell-autonomous fashion through regulation of Kv1 channel expression at the soma membrane. This is the first example of passive transfer of an autoimmune peripheral neuropathic pain disorder and demonstrates that CASPR2 has a key role in regulating cell-intrinsic dorsal root ganglion (DRG) neuron excitability. Treatment with human CASPR2-Abs causes mechanical hypersensitivity in mice CASPR2-Abs remain PNS restricted and enhance pain behavior without neural injury Pain behavior is increased in Cntnap2−/− mice (lacking full-length CASPR2) CASPR2 regulates DRG cell excitability via Kv1 channel trafficking to the membrane
Collapse
|
11
|
Oertel D, Cao XJ, Ison JR, Allen PD. Cellular Computations Underlying Detection of Gaps in Sounds and Lateralizing Sound Sources. Trends Neurosci 2017; 40:613-624. [PMID: 28867348 DOI: 10.1016/j.tins.2017.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [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: 04/25/2017] [Revised: 08/02/2017] [Accepted: 08/07/2017] [Indexed: 11/29/2022]
Abstract
In mammals, acoustic information arises in the cochlea and is transmitted to the ventral cochlear nuclei (VCN). Three groups of VCN neurons extract different features from the firing of auditory nerve fibers and convey that information along separate pathways through the brainstem. Two of these pathways process temporal information: octopus cells detect coincident firing among auditory nerve fibers and transmit signals along monaural pathways, and bushy cells sharpen the encoding of fine structure and feed binaural pathways. The ability of these cells to signal with temporal precision depends on a low-voltage-activated K+ conductance (gKL) and a hyperpolarization-activated conductance (gh). This 'tale of two conductances' traces gap detection and sound lateralization to their cellular and biophysical origins.
Collapse
Affiliation(s)
- Donata Oertel
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53705 USA.
| | - Xiao-Jie Cao
- Department of Neuroscience, School of Medicine and Public Health, University of Wisconsin, Madison, WI 53705 USA
| | - James R Ison
- Department of Brain and Cognitive Sciences, Meliora Hall, University of Rochester, Rochester, NY 14627, USA; Department of Neuroscience, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Paul D Allen
- Department of Otolaryngology, University of Rochester Medical Center, Rochester, NY 14642, USA
| |
Collapse
|
12
|
Abstract
Classic hallucinogens share pharmacology as serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptor agonists. Unique among most other Schedule 1 drugs, they are generally non-addictive and can be effective tools in the treatment of addiction. Mechanisms underlying these attributes are largely unknown. However, many preclinical studies show that 5-HT2C agonists counteract the addictive effects of drugs from several classes, suggesting this pharmacological property of classic hallucinogens may be significant. Drawing from a comprehensive analysis of preclinical behavior, neuroanatomy, and neurochemistry studies, this review builds rationale for this hypothesis, and also proposes a testable, neurobiological framework. 5-HT2C agonists work, in part, by modulating dopamine neuron activity in the ventral tegmental area-nucleus accumbens (NAc) reward pathway. We argue that activation of 5-HT2C receptors on NAc shell, GABAergic, medium spiny neurons inhibits potassium Kv1.x channels, thereby enhancing inhibitory activity via intrinsic mechanisms. Together with experiments that show that addictive drugs, such as cocaine, potentiate Kv1.x channels, thereby suppressing NAc shell GABAergic activity, this hypothesis provides a mechanism by which classic hallucinogen-mediated stimulation of 5-HT2C receptors could thwart addiction. It also provides a potential reason for the non-addictive nature of classic hallucinogens.
Collapse
Affiliation(s)
- Clinton E Canal
- Center for Drug Discovery, Department of Pharmaceutical Sciences, Northeastern University, Boston, USA
| | - Kevin S Murnane
- Department of Pharmaceutical Sciences, Mercer University College of Pharmacy, Mercer University Health Sciences Center, Atlanta, USA
| |
Collapse
|
13
|
Fischl MJ, Burger RM, Schmidt-Pauly M, Alexandrova O, Sinclair JL, Grothe B, Forsythe ID, Kopp-Scheinpflug C. Physiology and anatomy of neurons in the medial superior olive of the mouse. J Neurophysiol 2016; 116:2676-2688. [PMID: 27655966 PMCID: PMC5133312 DOI: 10.1152/jn.00523.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [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: 06/29/2016] [Accepted: 09/19/2016] [Indexed: 12/16/2022] Open
Abstract
In mammals with good low-frequency hearing, the medial superior olive (MSO) computes sound location by comparing differences in the arrival time of a sound at each ear, called interaural time disparities (ITDs). Low-frequency sounds are not reflected by the head, and therefore level differences and spectral cues are minimal or absent, leaving ITDs as the only cue for sound localization. Although mammals with high-frequency hearing and small heads (e.g., bats, mice) barely experience ITDs, the MSO is still present in these animals. Yet, aside from studies in specialized bats, in which the MSO appears to serve functions other than ITD processing, it has not been studied in small mammals that do not hear low frequencies. Here we describe neurons in the mouse brain stem that share prominent anatomical, morphological, and physiological properties with the MSO in species known to use ITDs for sound localization. However, these neurons also deviate in some important aspects from the typical MSO, including a less refined arrangement of cell bodies, dendrites, and synaptic inputs. In vitro, the vast majority of neurons exhibited a single, onset action potential in response to suprathreshold depolarization. This spiking pattern is typical of MSO neurons in other species and is generated from a complement of Kv1, Kv3, and IH currents. In vivo, mouse MSO neurons show bilateral excitatory and inhibitory tuning as well as an improvement in temporal acuity of spiking during bilateral acoustic stimulation. The combination of classical MSO features like those observed in gerbils with more unique features similar to those observed in bats and opossums make the mouse MSO an interesting model for exploiting genetic tools to test hypotheses about the molecular mechanisms and evolution of ITD processing.
Collapse
Affiliation(s)
- Matthew J Fischl
- Division of Neurobiology, Department of Biology II, Ludwig Maximilian University Munich, Planegg-Martinsried, Germany
| | - R Michael Burger
- Department of Biological Sciences, Lehigh University, Bethlehem, Pennsylvania; and
| | - Myriam Schmidt-Pauly
- Division of Neurobiology, Department of Biology II, Ludwig Maximilian University Munich, Planegg-Martinsried, Germany
| | - Olga Alexandrova
- Division of Neurobiology, Department of Biology II, Ludwig Maximilian University Munich, Planegg-Martinsried, Germany
| | - James L Sinclair
- Division of Neurobiology, Department of Biology II, Ludwig Maximilian University Munich, Planegg-Martinsried, Germany
| | - Benedikt Grothe
- Division of Neurobiology, Department of Biology II, Ludwig Maximilian University Munich, Planegg-Martinsried, Germany
| | - Ian D Forsythe
- Department of Neuroscience, Psychology, and Behaviour, University of Leicester, Leicester, United Kingdom
| | - Conny Kopp-Scheinpflug
- Division of Neurobiology, Department of Biology II, Ludwig Maximilian University Munich, Planegg-Martinsried, Germany;
| |
Collapse
|
14
|
Doczi MA, Vitzthum CM, Forehand CJ. Developmental expression of Kv1 voltage-gated potassium channels in the avian hypothalamus. Neurosci Lett 2016; 616:182-8. [PMID: 26845562 DOI: 10.1016/j.neulet.2016.01.068] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 11/12/2015] [Revised: 01/07/2016] [Accepted: 01/29/2016] [Indexed: 02/07/2023]
Abstract
Specialized hypothalamic neurons integrate the homeostatic balance between food intake and energy expenditure, processes that may become dysregulated during the development of diabetes, obesity, and other metabolic disorders. Shaker family voltage-gated potassium channels (Kv1) contribute to the maintenance of resting membrane potential, action potential characteristics, and neurotransmitter release in many populations of neurons, although hypothalamic Kv1 channel expression has been largely unexplored. Whole-cell patch clamp recordings from avian hypothalamic brain slices demonstrate a developmental shift in the electrophysiological properties of avian arcuate nucleus neurons, identifying an increase in outward ionic current that corresponds with action potential maturation. Additionally, RT-PCR experiments identified the early expression of Kv1.2, Kv1.3, and Kv1.5 mRNA in the embryonic avian hypothalamus, suggesting that these channels may underlie the electrophysiological changes observed in these neurons. Real-time quantitative PCR analysis on intact microdissections of embryonic hypothalamic tissue revealed a concomitant increase in Kv1.2 and Kv1.5 gene expression at key electrophysiological time points during development. This study is the first to demonstrate hypothalamic mRNA expression of Kv1 channels in developing avian embryos and may suggest a role for voltage-gated ion channel regulation in the physiological patterning of embryonic hypothalamic circuits governing energy homeostasis.
Collapse
Affiliation(s)
- Megan A Doczi
- Norwich University, 158 Harmon Drive, Northfield, VT 05663, USA.
| | - Carl M Vitzthum
- Norwich University, 158 Harmon Drive, Northfield, VT 05663, USA
| | - Cynthia J Forehand
- The University of Vermont, 189 Beaumont Avenue, Burlington, VT 05405, USA
| |
Collapse
|
15
|
Rama S, Zbili M, Debanne D. Modulation of spike-evoked synaptic transmission: The role of presynaptic calcium and potassium channels. Biochim Biophys Acta 2015; 1853:1933-9. [PMID: 25461842 DOI: 10.1016/j.bbamcr.2014.11.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 11/17/2014] [Accepted: 11/19/2014] [Indexed: 01/08/2023]
Abstract
Action potentials are usually considered as the smallest unit of neuronal information conveyed by presynaptic neurons to their postsynaptic target. Thus, neuronal signaling in brain circuits is all-or-none or digital. However, recent studies indicate that subthreshold analog variation in presynaptic membrane potential modulates spike-evoked transmission. The informational content of each presynaptic action potential is therefore greater than initially expected. This property constitutes a form of fast activity-dependent modulation of functional coupling. Therefore, it could have important consequences on information processing in neural networks in parallel with more classical forms of presynaptic short-term facilitation based on repetitive stimulation, modulation of presynaptic calcium or modifications of the release machinery. We discuss here how analog voltage shift in the presynaptic neuron may regulate spike-evoked release of neurotransmitter through the modulation of voltage-gated calcium and potassium channels in the axon and presynaptic terminal. This article is part of a Special Issue entitled: 13th European Symposium on Calcium.
Collapse
|