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Liénard MA, Baez-Nieto D, Tsai CC, Valencia-Montoya WA, Werin B, Johanson U, Lassance JM, Pan JQ, Yu N, Pierce NE. TRPA5 encodes a thermosensitive ankyrin ion channel receptor in a triatomine insect. iScience 2024; 27:109541. [PMID: 38577108 PMCID: PMC10993193 DOI: 10.1016/j.isci.2024.109541] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 02/28/2024] [Accepted: 03/18/2024] [Indexed: 04/06/2024] Open
Abstract
As ectotherms, insects need heat-sensitive receptors to monitor environmental temperatures and facilitate thermoregulation. We show that TRPA5, a class of ankyrin transient receptor potential (TRP) channels absent in dipteran genomes, may function as insect heat receptors. In the triatomine bug Rhodnius prolixus (order: Hemiptera), a vector of Chagas disease, the channel RpTRPA5B displays a uniquely high thermosensitivity, with biophysical determinants including a large channel activation enthalpy change (72 kcal/mol), a high temperature coefficient (Q10 = 25), and in vitro temperature-induced currents from 53°C to 68°C (T0.5 = 58.6°C), similar to noxious TRPV receptors in mammals. Monomeric and tetrameric ion channel structure predictions show reliable parallels with fruit fly dTRPA1, with structural uniqueness in ankyrin repeat domains, the channel selectivity filter, and potential TRP functional modulator regions. Overall, the finding of a member of TRPA5 as a temperature-activated receptor illustrates the diversity of insect molecular heat detectors.
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Affiliation(s)
- Marjorie A. Liénard
- Department of Biology, Lund University, 22362 Lund, Sweden
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
- Broad Institute, Cambridge, MA 02142, USA
| | - David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA 02142, USA
| | - Cheng-Chia Tsai
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, USA
| | - Wendy A. Valencia-Montoya
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
| | - Balder Werin
- Division of Biochemistry and Structural Biology, Department of Chemistry, Lund University, 22362 Lund, Sweden
| | - Urban Johanson
- Division of Biochemistry and Structural Biology, Department of Chemistry, Lund University, 22362 Lund, Sweden
| | - Jean-Marc Lassance
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
- Laboratory of Evolutionary Neuroethology, GIGA Institute, University of Liège, 4000 Liège, Belgium
| | - Jen Q. Pan
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA 02142, USA
| | - Nanfang Yu
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, NY 10027, USA
| | - Naomi E. Pierce
- Department of Organismic and Evolutionary Biology and Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
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2
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Shepard N, Baez-Nieto D, Iqbal S, Kurganov E, Budnik N, Campbell AJ, Pan JQ, Sheng M, Farsi Z. Differential functional consequences of GRIN2A mutations associated with schizophrenia and neurodevelopmental disorders. Sci Rep 2024; 14:2798. [PMID: 38307912 PMCID: PMC10837427 DOI: 10.1038/s41598-024-53102-3] [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: 08/01/2023] [Accepted: 01/27/2024] [Indexed: 02/04/2024] Open
Abstract
Human genetic studies have revealed rare missense and protein-truncating variants in GRIN2A, encoding for the GluN2A subunit of the NMDA receptors, that confer significant risk for schizophrenia (SCZ). Mutations in GRIN2A are also associated with epilepsy and developmental delay/intellectual disability (DD/ID). However, it remains enigmatic how alterations to the same protein can result in diverse clinical phenotypes. Here, we performed functional characterization of human GluN1/GluN2A heteromeric NMDA receptors that contain SCZ-linked GluN2A variants, and compared them to NMDA receptors with GluN2A variants associated with epilepsy or DD/ID. Our findings demonstrate that SCZ-associated GRIN2A variants were predominantly loss-of-function (LoF), whereas epilepsy and DD/ID-associated variants resulted in both gain- and loss-of-function phenotypes. We additionally show that M653I and S809R, LoF GRIN2A variants associated with DD/ID, exert a dominant-negative effect when co-expressed with a wild-type GluN2A, whereas E58Ter and Y698C, SCZ-linked LoF variants, and A727T, an epilepsy-linked LoF variant, do not. These data offer a potential mechanism by which SCZ/epilepsy and DD/ID-linked variants can cause different effects on receptor function and therefore result in divergent pathological outcomes.
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Affiliation(s)
- Nate Shepard
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Sumaiya Iqbal
- The Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Erkin Kurganov
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Nikita Budnik
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Arthur J Campbell
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jen Q Pan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Morgan Sheng
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
| | - Zohreh Farsi
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
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3
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Baez-Nieto D, Allen A, Akers-Campbell S, Yang L, Budnik N, Pupo A, Shin YC, Genovese G, Liao M, Pérez-Palma E, Heyne H, Lal D, Lipscombe D, Pan JQ. Analysing an allelic series of rare missense variants of CACNA1I in a Swedish schizophrenia cohort. Brain 2022; 145:1839-1853. [PMID: 34919654 PMCID: PMC9166571 DOI: 10.1093/brain/awab443] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [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: 07/19/2021] [Revised: 10/23/2021] [Accepted: 11/11/2021] [Indexed: 11/14/2022] Open
Abstract
CACNA1I is implicated in the susceptibility to schizophrenia by large-scale genetic association studies of single nucleotide polymorphisms. However, the channelopathy of CACNA1I in schizophrenia is unknown. CACNA1I encodes CaV3.3, a neuronal voltage-gated calcium channel that underlies a subtype of T-type current that is important for neuronal excitability in the thalamic reticular nucleus and other regions of the brain. Here, we present an extensive functional characterization of 57 naturally occurring rare and common missense variants of CACNA1I derived from a Swedish schizophrenia cohort of more than 10 000 individuals. Our analysis of this allelic series of coding CACNA1I variants revealed that reduced CaV3.3 channel current density was the dominant phenotype associated with rare CACNA1I coding alleles derived from control subjects, whereas rare CACNA1I alleles from schizophrenia patients encoded CaV3.3 channels with altered responses to voltages. CACNA1I variants associated with altered current density primarily impact the ionic channel pore and those associated with altered responses to voltage impact the voltage-sensing domain. CaV3.3 variants associated with altered voltage dependence of the CaV3.3 channel and those associated with peak current density deficits were significantly segregated across affected and unaffected groups (Fisher's exact test, P = 0.034). Our results, together with recent data from the SCHEMA (Schizophrenia Exome Sequencing Meta-Analysis) cohort, suggest that reduced CaV3.3 function may protect against schizophrenia risk in rare cases. We subsequently modelled the effect of the biophysical properties of CaV3.3 channel variants on thalamic reticular nucleus excitability and found that compared with common variants, ultrarare CaV3.3-coding variants derived from control subjects significantly decreased thalamic reticular nucleus excitability (P = 0.011). When all rare variants were analysed, there was a non-significant trend between variants that reduced thalamic reticular nucleus excitability and variants that either had no effect or increased thalamic reticular nucleus excitability across disease status. Taken together, the results of our functional analysis of an allelic series of >50 CACNA1I variants in a schizophrenia cohort reveal that loss of function of CaV3.3 is a molecular phenotype associated with reduced disease risk burden, and our approach may serve as a template strategy for channelopathies in polygenic disorders.
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Affiliation(s)
- David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Andrew Allen
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Seth Akers-Campbell
- Carney Institute for Brain Science & Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Lingling Yang
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Nikita Budnik
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Amaury Pupo
- Department of Biology, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Young-Cheul Shin
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Giulio Genovese
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
| | - Maofu Liao
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Eduardo Pérez-Palma
- Genomic Medicine Institute, Lerner Research institute, Cleveland Clinic, OH 44195, USA
- Centro de Genética y Genómica, Universidad del Desarrollo, Centro de Genética y Genómica, Facultad de Medicina Clínica Alemana, Chile
| | - Henrike Heyne
- Genomic Medicine, Hasso Plattner Institute, Potsdam, 14482, Germany
| | - Dennis Lal
- Genomic Medicine Institute, Lerner Research institute, Cleveland Clinic, OH 44195, USA
- Cologne Center for Genomics, University of Cologne, Cologne 50931, Germany
- Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH 44195, USA
| | - Diane Lipscombe
- Carney Institute for Brain Science & Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Jen Q. Pan
- Stanley Center for Psychiatric Research, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA
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4
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Zhang YL, Moran SP, Allen A, Baez-Nieto D, Xu Q, Wang LA, Martenis WE, Sacher JR, Gale JP, Weïwer M, Wagner FF, Pan JQ. Novel Fluorescence-Based High-Throughput FLIPR Assay Utilizing Membrane-Tethered Genetic Calcium Sensors to Identify T-Type Calcium Channel Modulators. ACS Pharmacol Transl Sci 2022; 5:156-168. [PMID: 35311021 PMCID: PMC8923061 DOI: 10.1021/acsptsci.1c00233] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Indexed: 11/28/2022]
Abstract
T-type voltage-gated Ca2+ channels have been implicated in many human disorders, and there has been increasing interest in developing highly selective and potent T-type Ca2+ channel modulators for potential clinical use. However, the unique biophysical properties of T-type Ca2+ channels are not conducive for developing high-throughput screening (HTS) assays to identify modulators, particularly potentiators. To illustrate, T-type Ca2+ channels are largely inactivated and unable to open to allow Ca2+ influx at -25 mV, the typical resting membrane potential of the cell lines commonly used in cellular screening assays. To address this issue, we developed cell lines that express Kir2.3 channels to hyperpolarize the membrane potential to -70 mV, thus allowing T-type channels to return to their resting state where they can be subsequently activated by membrane depolarization in the presence of extracellular KCl. Furthermore, to simplify the HTS assay and to reduce reagent cost, we stably expressed a membrane-tethered genetic calcium sensor, GCaMP6s-CAAX, that displays superior signal to the background compared to the untethered GCaMP6s or the synthetic Ca2+ sensor Fluo-4AM. Here, we describe a novel GCaMP6s-CAAX-based calcium assay utilizing a high-throughput fluorometric imaging plate reader (Molecular Devices, Sunnyvale, CA) format that can identify both activators and inhibitors of T-type Ca2+ channels. Lastly, we demonstrate the utility of this novel fluorescence-based assay to evaluate the activities of two distinct G-protein-coupled receptors, thus expanding the use of GCaMP6s-CAAX to a wide range of applications relevant for developing cellular assays in drug discovery.
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5
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Heyne HO, Baez-Nieto D, Iqbal S, Palmer DS, Brunklaus A, May P, Johannesen KM, Lauxmann S, Lemke JR, Møller RS, Pérez-Palma E, Scholl UI, Syrbe S, Lerche H, Lal D, Campbell AJ, Wang HR, Pan J, Daly MJ. Predicting functional effects of missense variants in voltage-gated sodium and calcium channels. Sci Transl Med 2020; 12:12/556/eaay6848. [PMID: 32801145 DOI: 10.1126/scitranslmed.aay6848] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 11/20/2019] [Accepted: 07/22/2020] [Indexed: 12/30/2022]
Abstract
Malfunctions of voltage-gated sodium and calcium channels (encoded by SCNxA and CACNA1x family genes, respectively) have been associated with severe neurologic, psychiatric, cardiac, and other diseases. Altered channel activity is frequently grouped into gain or loss of ion channel function (GOF or LOF, respectively) that often corresponds not only to clinical disease manifestations but also to differences in drug response. Experimental studies of channel function are therefore important, but laborious and usually focus only on a few variants at a time. On the basis of known gene-disease mechanisms of 19 different diseases, we inferred LOF (n = 518) and GOF (n = 309) likely pathogenic variants from the disease phenotypes of variant carriers. By training a machine learning model on sequence- and structure-based features, we predicted LOF or GOF effects [area under the receiver operating characteristics curve (ROC) = 0.85] of likely pathogenic missense variants. Our LOF versus GOF prediction corresponded to molecular LOF versus GOF effects for 87 functionally tested variants in SCN1/2/8A and CACNA1I (ROC = 0.73) and was validated in exome-wide data from 21,703 cases and 128,957 controls. We showed respective regional clustering of inferred LOF and GOF nucleotide variants across the alignment of the entire gene family, suggesting shared pathomechanisms in the SCNxA/CACNA1x family genes.
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Affiliation(s)
- Henrike O Heyne
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA. .,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Institute for Molecular Medicine Finland (FIMM), University of Helsinki, 5WR36M Helsinki, Finland
| | - David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Sumaiya Iqbal
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Center for Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Duncan S Palmer
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Andreas Brunklaus
- Paediatric Neurosciences Research Group, Royal Hospital for Sick Children, Glasgow G51 4TF, UK.,School of Medicine, University of Glasgow, Glasgow G12 8QQ, UK
| | - Patrick May
- Luxembourg Centre for Systems Biomedicine, Belvaux, University of Luxembourg, 4365 Esch-sur-Alzette, Luxembourg
| | | | - Katrine M Johannesen
- Department of Epilepsy Genetics and Personalized Treatment, Danish Epilepsy Centre, 4293 Dianalund, Denmark.,Department of Regional Health Research, University of Southern Denmark, 5230 Odense, Denmark
| | - Stephan Lauxmann
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72076 Tuebingen, Germany
| | - Johannes R Lemke
- Institute of Human Genetics, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Rikke S Møller
- Department of Epilepsy Genetics and Personalized Treatment, Danish Epilepsy Centre, 4293 Dianalund, Denmark.,Department of Regional Health Research, University of Southern Denmark, 5230 Odense, Denmark
| | - Eduardo Pérez-Palma
- Cologne Center for Genomics (CCG), University of Cologne, 50923, Germany.,Genomic Medicine Institute, Lemer Research Institute Cleveland Clinic, OH G92J47, USA
| | - Ute I Scholl
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Department of Nephrology and Medical Intensive Care and BIH Center for Regenerative Therapies, 10178 Berlin, Germany.,Berlin Institute of Health (BIH), 10178 Berlin, Germany
| | - Steffen Syrbe
- Division of Pediatric Epileptology, Center for Paediatrics and Adolescent Medicine, University Hospital Heidelberg, 69120 Heidelberg, Germany
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tuebingen, 72076 Tuebingen, Germany
| | - Dennis Lal
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Cologne Center for Genomics (CCG), University of Cologne, 50923, Germany.,Genomic Medicine Institute, Lemer Research Institute Cleveland Clinic, OH G92J47, USA.,Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, OH G92J47, USA
| | - Arthur J Campbell
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Center for Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Hao-Ran Wang
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jen Pan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Mark J Daly
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, MA 02114, USA. .,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Institute for Molecular Medicine Finland (FIMM), University of Helsinki, 5WR36M Helsinki, Finland
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6
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Brunklaus A, Du J, Steckler F, Ghanty II, Johannesen KM, Fenger CD, Schorge S, Baez-Nieto D, Wang HR, Allen A, Pan JQ, Lerche H, Heyne H, Symonds JD, Zuberi SM, Sanders S, Sheidley BR, Craiu D, Olson HE, Weckhuysen S, DeJonge P, Helbig I, Van Esch H, Busa T, Milh M, Isidor B, Depienne C, Poduri A, Campbell AJ, Dimidschstein J, Møller RS, Lal D. Biological concepts in human sodium channel epilepsies and their relevance in clinical practice. Epilepsia 2020; 61:387-399. [PMID: 32090326 DOI: 10.1111/epi.16438] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [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: 09/09/2019] [Revised: 01/06/2020] [Accepted: 01/06/2020] [Indexed: 01/07/2023]
Abstract
OBJECTIVE Voltage-gated sodium channels (SCNs) share similar amino acid sequence, structure, and function. Genetic variants in the four human brain-expressed SCN genes SCN1A/2A/3A/8A have been associated with heterogeneous epilepsy phenotypes and neurodevelopmental disorders. To better understand the biology of seizure susceptibility in SCN-related epilepsies, our aim was to determine similarities and differences between sodium channel disorders, allowing us to develop a broader perspective on precision treatment than on an individual gene level alone. METHODS We analyzed genotype-phenotype correlations in large SCN-patient cohorts and applied variant constraint analysis to identify severe sodium channel disease. We examined temporal patterns of human SCN expression and correlated functional data from in vitro studies with clinical phenotypes across different sodium channel disorders. RESULTS Comparing 865 epilepsy patients (504 SCN1A, 140 SCN2A, 171 SCN8A, four SCN3A, 46 copy number variation [CNV] cases) and analysis of 114 functional studies allowed us to identify common patterns of presentation. All four epilepsy-associated SCN genes demonstrated significant constraint in both protein truncating and missense variation when compared to other SCN genes. We observed that age at seizure onset is related to SCN gene expression over time. Individuals with gain-of-function SCN2A/3A/8A missense variants or CNV duplications share similar characteristics, most frequently present with early onset epilepsy (<3 months), and demonstrate good response to sodium channel blockers (SCBs). Direct comparison of corresponding SCN variants across different SCN subtypes illustrates that the functional effects of variants in corresponding channel locations are similar; however, their clinical manifestation differs, depending on their role in different types of neurons in which they are expressed. SIGNIFICANCE Variant function and location within one channel can serve as a surrogate for variant effects across related sodium channels. Taking a broader view on precision treatment suggests that in those patients with a suspected underlying genetic epilepsy presenting with neonatal or early onset seizures (<3 months), SCBs should be considered.
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Affiliation(s)
- Andreas Brunklaus
- Paediatric Neurosciences Research Group, Royal Hospital for Children, Glasgow, UK.,School of Medicine, University of Glasgow, Glasgow, UK
| | - Juanjiangmeng Du
- Cologne Center for Genomics, University of Cologne, University Hospital Cologne, Cologne, Germany
| | - Felix Steckler
- Paediatric Neurosciences Research Group, Royal Hospital for Children, Glasgow, UK.,School of Medicine, University of Glasgow, Glasgow, UK
| | - Ismael I Ghanty
- Paediatric Neurosciences Research Group, Royal Hospital for Children, Glasgow, UK.,School of Medicine, University of Glasgow, Glasgow, UK
| | - Katrine M Johannesen
- Deparment of Epilepsy Genetics and Personalized Medicine, Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Christina Dühring Fenger
- Deparment of Epilepsy Genetics and Personalized Medicine, Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,Amplexa Genetics, Odense, Denmark
| | - Stephanie Schorge
- Department of Clinical and Experimental Epilepsy, Institute of Neurology, University College London, London, UK.,School of Pharmacy, University College London, London, UK
| | - David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts
| | - Hao-Ran Wang
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts
| | - Andrew Allen
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts
| | - Jen Q Pan
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie Institute for Clinical Brain Research, University of Tübingen, Germany
| | - Henrike Heyne
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts.,Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Massachusetts.,Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | - Joseph D Symonds
- Paediatric Neurosciences Research Group, Royal Hospital for Children, Glasgow, UK.,School of Medicine, University of Glasgow, Glasgow, UK
| | - Sameer M Zuberi
- Paediatric Neurosciences Research Group, Royal Hospital for Children, Glasgow, UK.,School of Medicine, University of Glasgow, Glasgow, UK
| | - Stephan Sanders
- Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California
| | - Beth R Sheidley
- Epilepsy Genetics Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - Dana Craiu
- Carol Davila University of Medicine, Department of Clinical Neurosciences, Pediatric Neurology Discipline, Bucharest, Romania.,Alexandru Obregia Hospital, Pediatric Neurology Clinic, Bucharest, Romania
| | - Heather E Olson
- Epilepsy Genetics Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts
| | - Sarah Weckhuysen
- Neurogenetics Group, Center for Molecular Neurology, VIB, Antwerp, Belgium.,Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.,Department of Neurology, University Hospital Antwerp, Antwerp, Belgium
| | - Peter DeJonge
- Neurogenetics Group, Center for Molecular Neurology, VIB, Antwerp, Belgium.,Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.,Department of Neurology, University Hospital Antwerp, Antwerp, Belgium
| | - Ingo Helbig
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.,Department of Neuropediatrics, University of Kiel, Kiel, Germany
| | - Hilde Van Esch
- Department of Human Genetics and Center for Human Genetics, Laboratory for Genetics of Cognition, University Hospitals Leuven, Leuven, Belgium
| | - Tiffany Busa
- Genetics Department, Timone Enfants University Hospital Center, Public Assistance-Marseille Hospitals, Marseille, France
| | - Matthieu Milh
- Medical Genetics and Functional Genomics, National Institute of Health and Medical Research, Mixed Unit of Research S910, Aix-Marseille University, Marseille, France.,Hematology Laboratory, Le Mans Hospital Center, Le Mans, France
| | - Bertrand Isidor
- Medical Genetics Department, Nantes University Hospital Center, Nantes, France
| | - Christel Depienne
- Institute of Human Genetics, Essen University Hospital, Essen, Germany.,Brain and Spinal Cord Institute, National Institute of Health and Medical Research, Unit 1127, National Center for Scientific Research, Mixed Unit of Research 7225, Sorbonne Universities, Pierre and Marie Curie University, Mixed Unit of Research S 1127, Brain & Spine Institute, Paris, France
| | - Annapurna Poduri
- Epilepsy Genetics Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts
| | | | - Jordane Dimidschstein
- Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts
| | - Rikke S Møller
- Deparment of Epilepsy Genetics and Personalized Medicine, Danish Epilepsy Center Filadelfia, Dianalund, Denmark.,Institute for Regional Health Services, University of Southern Denmark, Odense, Denmark
| | - Dennis Lal
- Cologne Center for Genomics, University of Cologne, University Hospital Cologne, Cologne, Germany.,Stanley Center for Psychiatric Research, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts.,Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Massachusetts.,Epilepsy Center, Neurological Institute, Cleveland Clinic, Cleveland, Ohio.,Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio
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7
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Ghoshal A, Uygun DS, Yang L, McNally JM, Lopez-Huerta VG, Arias-Garcia MA, Baez-Nieto D, Allen A, Fitzgerald M, Choi S, Zhang Q, Hope JM, Yan K, Mao X, Nicholson TB, Imaizumi K, Fu Z, Feng G, Brown RE, Strecker RE, Purcell SM, Pan JQ. Effects of a patient-derived de novo coding alteration of CACNA1I in mice connect a schizophrenia risk gene with sleep spindle deficits. Transl Psychiatry 2020; 10:29. [PMID: 32066662 PMCID: PMC7026444 DOI: 10.1038/s41398-020-0685-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 10/25/2019] [Accepted: 11/06/2019] [Indexed: 11/09/2022] Open
Abstract
CACNA1I, a schizophrenia risk gene, encodes a subtype of voltage-gated T-type calcium channel CaV3.3. We previously reported that a patient-derived missense de novo mutation (R1346H) of CACNA1I impaired CaV3.3 channel function. Here, we generated CaV3.3-RH knock-in animals, along with mice lacking CaV3.3, to investigate the biological impact of R1346H (RH) variation. We found that RH mutation altered cellular excitability in the thalamic reticular nucleus (TRN), where CaV3.3 is abundantly expressed. Moreover, RH mutation produced marked deficits in sleep spindle occurrence and morphology throughout non-rapid eye movement (NREM) sleep, while CaV3.3 haploinsufficiency gave rise to largely normal spindles. Therefore, mice harboring the RH mutation provide a patient derived genetic model not only to dissect the spindle biology but also to evaluate the effects of pharmacological reagents in normalizing sleep spindle deficits. Importantly, our analyses highlighted the significance of characterizing individual spindles and strengthen the inferences we can make across species over sleep spindles. In conclusion, this study established a translational link between a genetic allele and spindle deficits during NREM observed in schizophrenia patients, representing a key step toward testing the hypothesis that normalizing spindles may be beneficial for schizophrenia patients.
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Affiliation(s)
- Ayan Ghoshal
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - David S. Uygun
- grid.410370.10000 0004 4657 1992Department of Psychiatry, VA Boston Healthcare System & Harvard Medical School, Boston, MA USA
| | - Lingling Yang
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - James M. McNally
- grid.410370.10000 0004 4657 1992Department of Psychiatry, VA Boston Healthcare System & Harvard Medical School, Boston, MA USA
| | - Violeta G. Lopez-Huerta
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA ,grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, MIT, Cambridge, MA USA ,grid.9486.30000 0001 2159 0001Present Address: Department of Neurodevelopment and Physiology, Institute of Cellular Physiology, National Autonomous University of Mexico, Mexico City, Mexico
| | - Mario A. Arias-Garcia
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA ,grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, MIT, Cambridge, MA USA ,grid.9486.30000 0001 2159 0001Present Address: Department of Neurodevelopment and Physiology, Institute of Cellular Physiology, National Autonomous University of Mexico, Mexico City, Mexico
| | - David Baez-Nieto
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - Andrew Allen
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - Megan Fitzgerald
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - Soonwook Choi
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA ,grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, MIT, Cambridge, MA USA
| | - Qiangge Zhang
- grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, MIT, Cambridge, MA USA
| | - Jen M. Hope
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - Karena Yan
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
| | - Xiaohong Mao
- grid.418424.f0000 0004 0439 2056Novartis Institutes for BioMedical Research, 181 Mass Ave., Cambridge, MA 02139 USA
| | - Thomas B. Nicholson
- grid.418424.f0000 0004 0439 2056Novartis Institutes for BioMedical Research, 181 Mass Ave., Cambridge, MA 02139 USA
| | - Kazuo Imaizumi
- grid.38142.3c000000041936754XWyss Institute, Harvard University, Cambridge, MA USA
| | - Zhanyan Fu
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA ,grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, MIT, Cambridge, MA USA
| | - Guoping Feng
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA ,grid.116068.80000 0001 2341 2786McGovern Institute for Brain Research, MIT, Cambridge, MA USA
| | - Ritchie E. Brown
- grid.410370.10000 0004 4657 1992Department of Psychiatry, VA Boston Healthcare System & Harvard Medical School, Boston, MA USA
| | - Robert E. Strecker
- grid.410370.10000 0004 4657 1992Department of Psychiatry, VA Boston Healthcare System & Harvard Medical School, Boston, MA USA
| | - Shaun M. Purcell
- grid.38142.3c000000041936754XBrigham and Women’s Hospital, Harvard Medical School, Boston, MA USA
| | - Jen Q. Pan
- grid.66859.34Stanley Center for Psychiatric Research, Broad Institute, Cambridge, MA USA
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Lu C, Shi X, Allen A, Baez-Nieto D, Nikish A, Sanjana NE, Pan JQ. Overexpression of NEUROG2 and NEUROG1 in human embryonic stem cells produces a network of excitatory and inhibitory neurons. FASEB J 2019; 33:5287-5299. [PMID: 30698461 PMCID: PMC6436650 DOI: 10.1096/fj.201801110rr] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [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: 06/14/2018] [Accepted: 01/02/2019] [Indexed: 01/19/2023]
Abstract
Overexpression of mouse neurogenin ( Neurog) 2 alone or in combination with mouse Neurog2/1 in human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) can rapidly produce high-yield excitatory neurons. Here, we report a detailed characterization of human neuronal networks induced by the expression of human NEUROG2 together with human NEUROG2/1 in hESCs using molecular, cellular, and electrophysiological measurements over 60 d after induction. Both excitatory synaptic transmission and network firing activity increased over time. Strikingly, inhibitory synaptic transmission and GABAergic cells were identified from NEUROG2/1 induced neurons (iNs). To illustrate the application of such iNs, we demonstrated that the heterozygous knock out of SCN2A, whose loss-of-function mutation is strongly implicated in autism risk, led to a dramatic reduction in network activity in the NEUROG2/1 iNs. Our findings not only extend our understanding of the NEUROG2/1-induced human neuronal network but also substantiate NEUROG2/1 iNs as an in vitro system for modeling neuronal and functional deficits on a human genetic background.-Lu, C., Shi, X., Allen, A., Baez-Nieto, D., Nikish, A., Sanjana, N. E., Pan, J. Q. Overexpression of NEUROG2 and NEUROG1 in human embryonic stem cells produces a network of excitatory and inhibitory neurons.
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Affiliation(s)
- Congyi Lu
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
- New York Genome Center, New York, New York, USA
- McGovern Institute for Brain Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA
- Department of Biology, New York University, New York, New York, USA
| | - Xi Shi
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
- McGovern Institute for Brain Research, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA
| | - Andrew Allen
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
| | - David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
| | - Alexandria Nikish
- Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts, USA
| | - Neville E. Sanjana
- New York Genome Center, New York, New York, USA
- Department of Biology, New York University, New York, New York, USA
| | - Jen Q. Pan
- Stanley Center for Psychiatric Research, Broad Institute, Cambridge, Massachusetts, USA
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Carmona EM, Baez-Nieto D, Pupo A, Castillo K, Alvarez O, Neely A, Latorre R, Gonzalez C. Properties of the Voltage-Gated Proton Channel Gating Currents. Biophys J 2018. [DOI: 10.1016/j.bpj.2017.11.2986] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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10
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Abstract
Ion channels represent nearly a quarter of all targets that currently available medications modulate, and their dysfunction underlies increasing number of human diseases. Functional analysis of ion channels have traditionally been a bottleneck in large-scale analyses. Recent technological breakthroughs in automated planar electrophysiology have democratized the technique to enable high-throughput patch clamping at scale. In this chapter, we describe the methodology to perform a phenotypic screen on voltage-gated calcium channels across many different genetic coding variations and against small-molecule modulators. We first describe the procedures to establish inducible heterologous ion channel expression in HEK293 cells, where each cell incorporates one copy of a target protein cDNA-a step that is critical for producing stable and consistent expression of ion channels. We then describe the experimental and analytical methods for analyzing the function of ion channels using high-throughput planar electrophysiology.
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Affiliation(s)
- Jen Q Pan
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
| | - David Baez-Nieto
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Andrew Allen
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Hao-Ran Wang
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Jeffrey R Cottrell
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
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Castillo K, Pupo A, Baez-Nieto D, Contreras GF, Morera FJ, Neely A, Latorre R, Gonzalez C. Voltage-gated proton (H(v)1) channels, a singular voltage sensing domain. FEBS Lett 2015; 589:3471-8. [PMID: 26296320 DOI: 10.1016/j.febslet.2015.08.003] [Citation(s) in RCA: 9] [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: 07/10/2015] [Revised: 08/10/2015] [Accepted: 08/11/2015] [Indexed: 12/28/2022]
Abstract
The main role of voltage-gated proton channels (Hv1) is to extrude protons from the intracellular milieu when, mediated by different cellular processes, the H(+) concentration increases. Hv1 are exquisitely selective for protons and their structure is homologous to the voltage sensing domain (VSD) of other voltage-gated ion channels like sodium, potassium, and calcium channels. In clear contrast to the classical voltage-dependent channels, Hv1 lacks a pore domain and thus permeation necessarily occurs through the voltage sensing domain. Hv1 channels are activated by depolarizing voltages, and increases in internal proton concentration. It has been proposed that local conformational changes of the transmembrane segment S4, driven by depolarization, trigger the molecular rearrangements that open Hv1. However, it is still unclear how the electromechanical coupling is achieved between the VSD and the potential pore, allowing the proton flux from the intracellular to the extracellular side. Here we provide a revised view of voltage activation in Hv1 channels, offering a comparative scenario with other voltage sensing channels domains.
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Affiliation(s)
- Karen Castillo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile
| | - Amaury Pupo
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile
| | - David Baez-Nieto
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile
| | - Gustavo F Contreras
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile
| | - Francisco J Morera
- Institute of Pharmacology and Morphophysiology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - Alan Neely
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile
| | - Ramon Latorre
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile.
| | - Carlos Gonzalez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360103, Chile.
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Pupo A, Baez-Nieto D, Martínez A, Latorre R, González C. Proton channel models filling the gap between experimental data and the structural rationale. Channels (Austin) 2015; 8:180-92. [PMID: 24755912 PMCID: PMC4203746 DOI: 10.4161/chan.28665] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Voltage-gated proton channels are integral membrane proteins with the capacity to permeate elementary particles in a voltage and pH dependent manner. These proteins have been found in several species and are involved in various physiological processes. Although their primary topology is known, lack of details regarding their structures in the open conformation has limited analyses toward a deeper understanding of the molecular determinants of their function and regulation. Consequently, the function-structure relationships have been inferred based on homology models. In the present work, we review the existing proton channel models, their assumptions, predictions and the experimental facts that support them. Modeling proton channels is not a trivial task due to the lack of a close homolog template. Hence, there are important differences between published models. This work attempts to critically review existing proton channel models toward the aim of contributing to a better understanding of the structural features of these proteins.
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Pinto BI, Baez-Nieto D, Pupo A, Martinez A, Latorre R, Gonzalez C. Residues Involved in Cx26 Hemichannels Voltage Dependent Gating. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.2415] [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: 11/15/2022] Open
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14
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Pupo A, Baez-Nieto D, Otarola E, Yañez O, Vergara-Jaque A, Gonzalez W, Castillo K, Contreras G, Larsson HP, Latorre R, Gonzalez C. Proton Permeation in Ci-Hv1 Voltage-Gated Proton Channels occurs through a Proton Wire Involving Residues D160 and D222 and It is Modulated by N264. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.2398] [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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Abstract
Potassium channels are particularly important in determining the shape and duration of the action potential, controlling the membrane potential, modulating hormone secretion, epithelial function and, in the case of those K(+) channels activated by Ca(2+), damping excitatory signals. The multiplicity of roles played by K(+) channels is only possible to their mammoth diversity that includes at present 70 K(+) channels encoding genes in mammals. Today, thanks to the use of cloning, mutagenesis, and the more recent structural studies using x-ray crystallography, we are in a unique position to understand the origins of the enormous diversity of this superfamily of ion channels, the roles they play in different cell types, and the relations that exist between structure and function. With the exception of two-pore K(+) channels that are dimers, voltage-dependent K(+) channels are tetrameric assemblies and share an extremely well conserved pore region, in which the ion-selectivity filter resides. In the present overview, we discuss in the function, localization, and the relations between function and structure of the five different subfamilies of K(+) channels: (a) inward rectifiers, Kir; (b) four transmembrane segments-2 pores, K2P; (c) voltage-gated, Kv; (d) the Slo family; and (e) Ca(2+)-activated SK family, SKCa.
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Affiliation(s)
- Carlos González
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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Baez-Nieto D, Alvarez O, Brauchi S, Gonzalez C, Latorre R. Voltage-Dependence in Thermo-Voltage Sensitive Channel TRPV1. A Delocalized Voltage Sensor? Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2525] [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: 10/27/2022] Open
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17
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Liu B, Baez-Nieto D, Qin F. Rapid Cooling Reveals the Closing Rate of TRPM8 to be Temperature-Dependent. Biophys J 2012. [DOI: 10.1016/j.bpj.2011.11.154] [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: 11/26/2022] Open
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