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Degalez F, Charles M, Foissac S, Zhou H, Guan D, Fang L, Klopp C, Allain C, Lagoutte L, Lecerf F, Acloque H, Giuffra E, Pitel F, Lagarrigue S. Enriched atlas of lncRNA and protein-coding genes for the GRCg7b chicken assembly and its functional annotation across 47 tissues. Sci Rep 2024; 14:6588. [PMID: 38504112 PMCID: PMC10951430 DOI: 10.1038/s41598-024-56705-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 03/09/2024] [Indexed: 03/21/2024] Open
Abstract
Gene atlases for livestock are steadily improving thanks to new genome assemblies and new expression data improving the gene annotation. However, gene content varies across databases due to differences in RNA sequencing data and bioinformatics pipelines, especially for long non-coding RNAs (lncRNAs) which have higher tissue and developmental specificity and are harder to consistently identify compared to protein coding genes (PCGs). As done previously in 2020 for chicken assemblies galgal5 and GRCg6a, we provide a new gene atlas, lncRNA-enriched, for the latest GRCg7b chicken assembly, integrating "NCBI RefSeq", "EMBL-EBI Ensembl/GENCODE" reference annotations and other resources such as FAANG and NONCODE. As a result, the number of PCGs increases from 18,022 (RefSeq) and 17,007 (Ensembl) to 24,102, and that of lncRNAs from 5789 (RefSeq) and 11,944 (Ensembl) to 44,428. Using 1400 public RNA-seq transcriptome representing 47 tissues, we provided expression evidence for 35,257 (79%) lncRNAs and 22,468 (93%) PCGs, supporting the relevance of this atlas. Further characterization including tissue-specificity, sex-differential expression and gene configurations are provided. We also identified conserved miRNA-hosting genes with human counterparts, suggesting common function. The annotated atlas is available at gega.sigenae.org.
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Affiliation(s)
- Fabien Degalez
- PEGASE, INRAE, Institut Agro, 35590, Saint Gilles, France
| | - Mathieu Charles
- INRAE, BioinfOmics, GenoToul Bioinformatics facility, Sigenae, Université Fédérale de Toulouse, 31326, Castanet-Tolosan, France
- INRAE, AgroParisTech, GABI, Paris-Saclay University, 78350, Jouy-en-Josas, France
| | - Sylvain Foissac
- GenPhySE, Université de Toulouse, INRAE, ENVT, 31326, Castanet-Tolosan, France
| | | | - Dailu Guan
- University of California Davis, Davis, USA
| | | | - Christophe Klopp
- INRAE, BioinfOmics, GenoToul Bioinformatics facility, Sigenae, Université Fédérale de Toulouse, 31326, Castanet-Tolosan, France
| | - Coralie Allain
- PEGASE, INRAE, Institut Agro, 35590, Saint Gilles, France
| | | | | | - Hervé Acloque
- INRAE, AgroParisTech, GABI, Paris-Saclay University, 78350, Jouy-en-Josas, France
| | - Elisabetta Giuffra
- INRAE, AgroParisTech, GABI, Paris-Saclay University, 78350, Jouy-en-Josas, France
| | - Frédérique Pitel
- GenPhySE, Université de Toulouse, INRAE, ENVT, 31326, Castanet-Tolosan, France
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Jacinto JGP, Bolcato M, Häfliger IM, Oevermann A, Gentile A, Drögemüller C. DYRK1B haploinsufficiency in a Holstein cattle with epilepsy. Anim Genet 2023; 54:623-627. [PMID: 37580898 DOI: 10.1111/age.13348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 07/16/2023] [Accepted: 07/22/2023] [Indexed: 08/16/2023]
Abstract
In this study, epilepsy with focal seizures progressing to generalized seizures was diagnosed in a 6-month-old Holstein heifer. The seizures were characterized by a brief pre-ictal phase with depression and vocalization. During the ictal phase eyelid spasms, tongue contractions, nodding and abundant salivation were observed, rapidly followed by a convulsive phase with bilateral tonic, clonic or tonic-clonic activity and loss of consciousness. Finally, during the postictal phase the heifer was obtunded and disorientated, unable to perceive obstacles and hypermetric, and pressed its head against objects. In the inter-seizure phase, the heifer was clinically normal. Neuropathology revealed axonal degeneration in the brainstem and diffuse astrocytic hypertrophic gliosis. Whole genome sequencing of the affected heifer identified a private heterozygous splice-site variant in DYRK1B (NM_001081515.1: c.-101-1G>A), most likely resulting in haploinsufficiency owing to loss-of-function. This represents a report of a DYRK1B-associated disease in cattle and adds DYRK1B to the candidate genes for epilepsy.
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Affiliation(s)
- Joana G P Jacinto
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Marilena Bolcato
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Irene M Häfliger
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Anna Oevermann
- Division of Neurological Sciences, DCR-VPH, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Arcangelo Gentile
- Department of Veterinary Medical Sciences, University of Bologna, Bologna, Italy
| | - Cord Drögemüller
- Institute of Genetics, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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3
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Badura-Stronka M, Kuszel Ł, Wencel-Warot A, Cudnoch K, Wołyńska K, Rutkowska K, Steinborn B, Płoski R. Broadening the phenotypic spectrum of the presumably epilepsy-related SV2A gene variants. Epilepsy Res 2023; 190:107101. [PMID: 36758444 DOI: 10.1016/j.eplepsyres.2023.107101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/14/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023]
Abstract
Missense variants in the synaptic vesicle glycoprotein SV2A gene have been previously found in a few individuals with epilepsy. Adverse reaction to levetiracetam in individuals with various variants of this gene has recently been described. Here, we report on a family with several members affected by epilepsy. In affected members of this family, we identified a variant in the SV2A gene (NM_014849.5: c.1978 G>A, p.(Gly660Arg). This family case further supports the role of the SV2A gene in autosomal dominant epilepsy. It provides new information on the course of epilepsy in people with variants in the SV2A gene who have never been treated with SV2A agonists and specific neurodevelopmental features of this syndrome.
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Affiliation(s)
- Magdalena Badura-Stronka
- Chair and Department of Medical Genetics, Poznan University of Medical Sciences, Poznań, Poland; Centers for Medical Genetics GENESIS, Poznan, Poland.
| | - Łukasz Kuszel
- Chair and Department of Medical Genetics, Poznan University of Medical Sciences, Poznań, Poland
| | - Agnieszka Wencel-Warot
- Department of Developmental Neurology, Poznan University of Medical Sciences, Poznań, Poland
| | - Kamila Cudnoch
- Department of Developmental Neurology, Poznan University of Medical Sciences, Poznań, Poland
| | - Katarzyna Wołyńska
- Chair and Department of Medical Genetics, Poznan University of Medical Sciences, Poznań, Poland
| | - Karolina Rutkowska
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
| | - Barbara Steinborn
- Department of Developmental Neurology, Poznan University of Medical Sciences, Poznań, Poland
| | - Rafał Płoski
- Department of Medical Genetics, Medical University of Warsaw, Warsaw, Poland
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4
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Myren‐Svelstad S, Jamali A, Ophus SS, D'gama PP, Ostenrath AM, Mutlu AK, Hoffshagen HH, Hotz AL, Neuhauss SCF, Jurisch‐Yaksi N, Yaksi E. Elevated photic response is followed by a rapid decay and depressed state in ictogenic networks. Epilepsia 2022; 63:2543-2560. [PMID: 36222083 PMCID: PMC9804334 DOI: 10.1111/epi.17380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 01/05/2023]
Abstract
OBJECTIVE The switch between nonseizure and seizure states involves profound alterations in network excitability and synchrony. In this study, we aimed to identify and compare features of neural excitability and dynamics across multiple zebrafish seizure and epilepsy models. METHODS Inspired by video-electroencephalographic recordings in patients, we developed a framework to study spontaneous and photically evoked neural and locomotor activity in zebrafish larvae, by combining high-throughput behavioral tracking and whole-brain in vivo two-photon calcium imaging. RESULTS Our setup allowed us to dissect behavioral and physiological features that are divergent or convergent across multiple models. We observed that spontaneous locomotor and neural activity exhibit great diversity across models. Nonetheless, during photic stimulation, hyperexcitability and rapid response dynamics were well conserved across multiple models, highlighting the reliability of photically evoked activity for high-throughput assays. Intriguingly, in several models, we observed that the initial elevated photic response is often followed by rapid decay of neural activity and a prominent depressed state. Elevated photic response and following depressed state in seizure-prone networks are significantly reduced by the antiseizure medication valproic acid. Finally, rapid decay and depression of neural activity following photic stimulation temporally overlap with slow recruitment of astroglial calcium signals that are enhanced in seizure-prone networks. SIGNIFICANCE We argue that fast decay of neural activity and depressed states following photic response are likely due to homeostatic mechanisms triggered by excessive neural activity. An improved understanding of the interplay between elevated and depressed excitability states might suggest tailored epilepsy therapies.
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Affiliation(s)
- Sverre Myren‐Svelstad
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Department of Neuromedicine and Movement Science, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Department of Neurology and Clinical NeurophysiologySt Olav's University HospitalTrondheimNorway
| | - Ahmed Jamali
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Department of Neuromedicine and Movement Science, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Department of Neurology and Clinical NeurophysiologySt Olav's University HospitalTrondheimNorway
| | - Sunniva S. Ophus
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway
| | - Percival P. D'gama
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Department of Clinical and Molecular Medicine, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway
| | - Anna M. Ostenrath
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway
| | - Aytac Kadir Mutlu
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway
| | - Helene Homme Hoffshagen
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway
| | - Adriana L. Hotz
- Department of Molecular Life SciencesUniversity of ZürichZürichSwitzerland
| | | | - Nathalie Jurisch‐Yaksi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Department of Neurology and Clinical NeurophysiologySt Olav's University HospitalTrondheimNorway,Department of Clinical and Molecular Medicine, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway
| | - Emre Yaksi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health SciencesNorwegian University of Science and TechnologyTrondheimNorway,Koç University Research Center for Translational Medicine, Department of NeurologyKoç University School of MedicineIstanbulTurkey
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5
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Zhang Y, Heylen L, Partoens M, Mills JD, Kaminski RM, Godard P, Gillard M, de Witte PAM, Siekierska A. Connectivity Mapping Using a Novel sv2a Loss-of-Function Zebrafish Epilepsy Model as a Powerful Strategy for Anti-epileptic Drug Discovery. Front Mol Neurosci 2022; 15:881933. [PMID: 35686059 PMCID: PMC9172968 DOI: 10.3389/fnmol.2022.881933] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/08/2022] [Indexed: 12/03/2022] Open
Abstract
Synaptic vesicle glycoprotein 2A (SV2A) regulates action potential-dependent neurotransmitter release and is commonly known as the primary binding site of an approved anti-epileptic drug, levetiracetam. Although several rodent knockout models have demonstrated the importance of SV2A for functional neurotransmission, its precise physiological function and role in epilepsy pathophysiology remains to be elucidated. Here, we present a novel sv2a knockout model in zebrafish, a vertebrate with complementary advantages to rodents. We demonstrated that 6 days post fertilization homozygous sv2a–/– mutant zebrafish larvae, but not sv2a+/– and sv2a+/+ larvae, displayed locomotor hyperactivity and spontaneous epileptiform discharges, however, no major brain malformations could be observed. A partial rescue of this epileptiform brain activity could be observed after treatment with two commonly used anti-epileptic drugs, valproic acid and, surprisingly, levetiracetam. This observation indicated that additional targets, besides Sv2a, maybe are involved in the protective effects of levetiracetam against epileptic seizures. Furthermore, a transcriptome analysis provided insights into the neuropathological processes underlying the observed epileptic phenotype. While gene expression profiling revealed only one differentially expressed gene (DEG) between wildtype and sv2a+/– larvae, there were 4386 and 3535 DEGs between wildtype and sv2a–/–, and sv2a+/– and sv2a–/– larvae, respectively. Pathway and gene ontology (GO) enrichment analysis between wildtype and sv2a–/– larvae revealed several pathways and GO terms enriched amongst up- and down-regulated genes, including MAPK signaling, synaptic vesicle cycle, and extracellular matrix organization, all known to be involved in epileptogenesis and epilepsy. Importantly, we used the Connectivity map database to identify compounds with opposing gene signatures compared to the one observed in sv2a–/– larvae, to finally rescue the epileptic phenotype. Two out of three selected compounds rescued electrographic discharges in sv2a–/– larvae, while negative controls did not. Taken together, our results demonstrate that sv2a deficiency leads to increased seizure vulnerability and provide valuable insight into the functional importance of sv2a in the brain in general. Furthermore, we provided evidence that the concept of connectivity mapping represents an attractive and powerful approach in the discovery of novel compounds against epilepsy.
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Affiliation(s)
- Yifan Zhang
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
| | - Lise Heylen
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
| | - Michèle Partoens
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
| | - James D. Mills
- Department of Neuropathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, United Kingdom
- Chalfont Centre for Epilepsy, Chalfont St Peter, United Kingdom
| | - Rafal M. Kaminski
- Department of Medicinal Chemistry, Faculty of Pharmacy, Jagiellonian University Medical College, Kraków, Poland
- UCB Pharma, Braine-l’Alleud, Belgium
| | | | | | - Peter A. M. de Witte
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
- *Correspondence: Peter A. M. de Witte,
| | - Aleksandra Siekierska
- Laboratory for Molecular Biodiscovery, KU Leuven, Leuven, Belgium
- Aleksandra Siekierska,
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6
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Rossi R, Arjmand S, Bærentzen SL, Gjedde A, Landau AM. Synaptic Vesicle Glycoprotein 2A: Features and Functions. Front Neurosci 2022; 16:864514. [PMID: 35573314 PMCID: PMC9096842 DOI: 10.3389/fnins.2022.864514] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/05/2022] [Indexed: 01/05/2023] Open
Abstract
In recent years, the field of neuroimaging dramatically moved forward by means of the expeditious development of specific radioligands of novel targets. Among these targets, the synaptic vesicle glycoprotein 2A (SV2A) is a transmembrane protein of synaptic vesicles, present in all synaptic terminals, irrespective of neurotransmitter content. It is involved in key functions of neurons, focused on the regulation of neurotransmitter release. The ubiquitous expression in gray matter regions of the brain is the basis of its candidacy as a marker of synaptic density. Following the development of molecules derived from the structure of the anti-epileptic drug levetiracetam, which selectively binds to SV2A, several radiolabeled markers have been synthetized to allow the study of SV2A distribution with positron emission tomography (PET). These radioligands permit the evaluation of in vivo changes of SV2A distribution held to be a potential measure of synaptic density in physiological and pathological conditions. The use of SV2A as a biomarker of synaptic density raises important questions. Despite numerous studies over the last decades, the biological function and the expressional properties of SV2A remain poorly understood. Some functions of SV2A were claimed, but have not been fully elucidated. While the expression of SV2A is ubiquitous, stronger associations between SV2A and Υ amino butyric acid (GABA)-ergic rather than glutamatergic synapses were observed in some brain structures. A further issue is the unclear interaction between SV2A and its tracers, which reflects a need to clarify what really is detected with neuroimaging tools. Here, we summarize the current knowledge of the SV2A protein and we discuss uncertain aspects of SV2A biology and physiology. As SV2A expression is ubiquitous, but likely more strongly related to a certain type of neurotransmission in particular circumstances, a more extensive knowledge of the protein would greatly facilitate the analysis and interpretation of neuroimaging results by allowing the evaluation not only of an increase or decrease of the protein level, but also of the type of neurotransmission involved.
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Affiliation(s)
- Rachele Rossi
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine and PET Center, Aarhus University Hospital, Aarhus, Denmark
| | - Shokouh Arjmand
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Simone Larsen Bærentzen
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine and PET Center, Aarhus University Hospital, Aarhus, Denmark
| | - Albert Gjedde
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark.,Department of Neurology and Neurosurgery, McGill University, Montreal, QC, Canada
| | - Anne M Landau
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.,Department of Nuclear Medicine and PET Center, Aarhus University Hospital, Aarhus, Denmark
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7
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Perspective: Chicken Models for Studying the Ontogenetic Origin of Neuropsychiatric Disorders. Biomedicines 2022; 10:biomedicines10051155. [PMID: 35625892 PMCID: PMC9138209 DOI: 10.3390/biomedicines10051155] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 05/13/2022] [Accepted: 05/15/2022] [Indexed: 12/29/2022] Open
Abstract
Nutrients and xenobiotics cross the blood–placenta barrier, potentially depositing in the fetal brain. The prenatal exposure affects the neuroendocrine and microbial development. The mechanism underlying maternal risk factors reprograming the microbiota–gut–brain axis with long-term effects on psychosocial behaviors in offspring is not clear. In humans, it is not possible to assess the nutrient or xenobiotic deposition in the fetal brain and gastrointestinal system for ethical reasons. Moreover, the maternal–fetal microbe transfer during gestation, natural labor, and breast-feeding constitutes the initial gut microbiome in the progeny, which is inevitable in the most widely utilized rodent models. The social predisposition in precocial birds, including chickens, provides the possibility to test behavioral responses shortly after being hatched. Hence, chickens are advantageous in investigating the ontogenetic origin of behaviors. Chicken embryos are suitable for deposition assessment and mechanistic study due to the accessibility, self-contained development, uniform genetic background, robust microbiota, and easy in vivo experimental manipulation compared to humans and rodents. Therefore, chicken embryos can be used as an alternative to the rodent models in assessing the fetal exposure effect on neurogenesis and investigating the mechanism underlying the ontogenetic origin of neuropsychiatric disorders.
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8
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Fisher RS, Acharya JN, Baumer FM, French JA, Parisi P, Solodar JH, Szaflarski JP, Thio LL, Tolchin B, Wilkins AJ, Kasteleijn-Nolst Trenité D. Visually sensitive seizures: An updated review by the Epilepsy Foundation. Epilepsia 2022; 63:739-768. [PMID: 35132632 DOI: 10.1111/epi.17175] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 01/10/2022] [Accepted: 01/12/2022] [Indexed: 12/19/2022]
Abstract
Light flashes, patterns, or color changes can provoke seizures in up to 1 in 4000 persons. Prevalence may be higher because of selection bias. The Epilepsy Foundation reviewed light-induced seizures in 2005. Since then, images on social media, virtual reality, three-dimensional (3D) movies, and the Internet have proliferated. Hundreds of studies have explored the mechanisms and presentations of photosensitive seizures, justifying an updated review. This literature summary derives from a nonsystematic literature review via PubMed using the terms "photosensitive" and "epilepsy." The photoparoxysmal response (PPR) is an electroencephalography (EEG) phenomenon, and photosensitive seizures (PS) are seizures provoked by visual stimulation. Photosensitivity is more common in the young and in specific forms of generalized epilepsy. PS can coexist with spontaneous seizures. PS are hereditable and linked to recently identified genes. Brain imaging usually is normal, but special studies imaging white matter tracts demonstrate abnormal connectivity. Occipital cortex and connected regions are hyperexcitable in subjects with light-provoked seizures. Mechanisms remain unclear. Video games, social media clips, occasional movies, and natural stimuli can provoke PS. Virtual reality and 3D images so far appear benign unless they contain specific provocative content, for example, flashes. Images with flashes brighter than 20 candelas/m2 at 3-60 (particularly 15-20) Hz occupying at least 10 to 25% of the visual field are a risk, as are red color flashes or oscillating stripes. Equipment to assay for these characteristics is probably underutilized. Prevention of seizures includes avoiding provocative stimuli, covering one eye, wearing dark glasses, sitting at least two meters from screens, reducing contrast, and taking certain antiseizure drugs. Measurement of PPR suppression in a photosensitivity model can screen putative antiseizure drugs. Some countries regulate media to reduce risk. Visually-induced seizures remain significant public health hazards so they warrant ongoing scientific and regulatory efforts and public education.
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Affiliation(s)
- Robert S Fisher
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California, USA
| | - Jayant N Acharya
- Department of Neurology, Penn State Health, Hershey, Pennsylvania, USA
| | - Fiona Mitchell Baumer
- Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, California, USA
| | - Jacqueline A French
- NYU Comprehensive Epilepsy Center, Epilepsy Foundation, New York, New York, USA
| | - Pasquale Parisi
- Department of Neuroscience, Mental Health, and Sensory Organs, Sapienza University, Rome, Italy
| | - Jessica H Solodar
- American Medical Writers Association-New England Chapter, Boston, Massachusetts, USA
| | - Jerzy P Szaflarski
- Department of Neurology, Neurobiology and Neurosurgery, University of Alabama at Birmingham Heersink School of Medicine, Birmingham, Alabama, USA
| | - Liu Lin Thio
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Benjamin Tolchin
- Department of Neurology, Yale School of Medicine, New Haven, Connecticut, USA
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9
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Gomes-Duarte A, Venø MT, de Wit M, Senthilkumar K, Broekhoven MH, van den Herik J, Heeres FR, van Rossum D, Rybiczka-Tesulov M, Legnini I, van Rijen PC, van Eijsden P, Gosselaar PH, Rajewsky N, Kjems J, Vangoor VR, Pasterkamp RJ. Expression of Circ_Satb1 Is Decreased in Mesial Temporal Lobe Epilepsy and Regulates Dendritic Spine Morphology. Front Mol Neurosci 2022; 15:832133. [PMID: 35310884 PMCID: PMC8927295 DOI: 10.3389/fnmol.2022.832133] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 02/10/2022] [Indexed: 11/24/2022] Open
Abstract
Mesial temporal lobe epilepsy (mTLE) is a chronic disease characterized by recurrent seizures that originate in the temporal lobes of the brain. Anti-epileptic drugs (AEDs) are the standard treatment for managing seizures in mTLE patients, but are frequently ineffective. Resective surgery is an option for some patients, but does not guarantee a postoperative seizure-free period. Therefore, further insight is needed into the pathogenesis of mTLE to enable the design of new therapeutic strategies. Circular RNAs (circRNAs) have been identified as important regulators of neuronal function and have been implicated in epilepsy. However, the mechanisms through which circRNAs contribute to epileptogenesis remain unknown. Here, we determine the circRNA transcriptome of the hippocampus and cortex of mTLE patients by using RNA-seq. We report 333 differentially expressed (DE) circRNAs between healthy individuals and mTLE patients, of which 23 circRNAs displayed significant adjusted p-values following multiple testing correction. Interestingly, hippocampal expression of circ_Satb1, a circRNA derived from special AT-rich sequence binding protein 1 (SATB1), is decreased in both mTLE patients and in experimental epilepsy. Our work shows that circ_Satb1 displays dynamic patterns of neuronal expression in vitro and in vivo. Further, circ_Satb1-specific knockdown using CRISPR/CasRx approaches in hippocampal cultures leads to defects in dendritic spine morphology, a cellular hallmark of mTLE. Overall, our results identify a novel epilepsy-associated circRNA with disease-specific expression and previously unidentified cellular effects that are relevant for epileptogenesis.
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Affiliation(s)
- Andreia Gomes-Duarte
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Morten T. Venø
- Interdisciplinary Nanoscience Center, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
- Omiics ApS, Aarhus, Denmark
| | - Marina de Wit
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Ketharini Senthilkumar
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Mark H. Broekhoven
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Joëlle van den Herik
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Fleur R. Heeres
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Daniëlle van Rossum
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Mateja Rybiczka-Tesulov
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Ivano Legnini
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Peter C. van Rijen
- Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Pieter van Eijsden
- Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Peter H. Gosselaar
- Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - Nikolaus Rajewsky
- Systems Biology of Gene Regulatory Elements, Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Jørgen Kjems
- Interdisciplinary Nanoscience Center, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Vamshidhar R. Vangoor
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
| | - R. Jeroen Pasterkamp
- Affiliated Partner of the European Reference Network EpiCARE, Department of Translational Neuroscience, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University, Utrecht, Netherlands
- *Correspondence: R. Jeroen Pasterkamp,
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Khateb M, Bosak N, Herskovitz M. The Effect of Anti-seizure Medications on the Propagation of Epileptic Activity: A Review. Front Neurol 2021; 12:674182. [PMID: 34122318 PMCID: PMC8191738 DOI: 10.3389/fneur.2021.674182] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/09/2021] [Indexed: 11/13/2022] Open
Abstract
The propagation of epileptiform events is a highly interesting phenomenon from the pathophysiological point of view, as it involves several mechanisms of recruitment of neural networks. Extensive in vivo and in vitro research has been performed, suggesting that multiple networks as well as cellular candidate mechanisms govern this process, including the co-existence of wave propagation, coupled oscillator dynamics, and more. The clinical importance of seizure propagation stems mainly from the fact that the epileptic manifestations cannot be attributed solely to the activity in the seizure focus itself, but rather to the propagation of epileptic activity to other brain structures. Propagation, especially when causing secondary generalizations, poses a risk to patients due to recurrent falls, traumatic injuries, and poor neurological outcome. Anti-seizure medications (ASMs) affect propagation in diverse ways and with different potencies. Importantly, for drug-resistant patients, targeting seizure propagation may improve the quality of life even without a major reduction in simple focal events. Motivated by the extensive impact of this phenomenon, we sought to review the literature regarding the propagation of epileptic activity and specifically the effect of commonly used ASMs on it. Based on this body of knowledge, we propose a novel classification of ASMs into three main categories: major, minor, and intermediate efficacy in reducing the propagation of epileptiform activity.
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Affiliation(s)
- Mohamed Khateb
- Department of Neurology, Rambam Health Care Campus, Haifa, Israel
| | - Noam Bosak
- Department of Neurology, Rambam Health Care Campus, Haifa, Israel
| | - Moshe Herskovitz
- Department of Neurology, Rambam Health Care Campus, Haifa, Israel.,The Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
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11
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Calame DG, Herman I, Riviello JJ. A de novo heterozygous rare variant in SV2A causes epilepsy and levetiracetam-induced drug-resistant status epilepticus. Epilepsy Behav Rep 2021; 15:100425. [PMID: 33554103 PMCID: PMC7844124 DOI: 10.1016/j.ebr.2020.100425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/23/2020] [Accepted: 12/28/2020] [Indexed: 11/01/2022] Open
Abstract
SV2A encodes a neuronal synaptic vesicle glycoprotein essential for neurotransmitter release. Altered SV2A function leads to epilepsy in animal models, yet only two reports of human variants have linked SV2A to syndromic drug-resistant epileptic encephalopathies and epilepsy. SV2A is also the binding site for the commonly used antiseizure medication levetiracetam (LEV). However, information about how rare SV2A variants influence LEV response is lacking. Here, we report a two-year-old child with new-onset epilepsy found to have a de novo heterozygous rare variant in SV2A (NM_014849.5:c.1978G>A;p.Gly660Arg) who developed refractory status epilepticus after escalation of LEV treatment for initial baseline seizure control. This report provides additional evidence that monoallelic pathogenic SV2A variants cause epilepsy and that genetic variation in SV2A could lead to paradoxical seizure worsening when treated with LEV.
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Affiliation(s)
- Daniel G Calame
- Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience, Baylor College of Medicine, Houston, TX 77030, United States
| | - Isabella Herman
- Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience, Baylor College of Medicine, Houston, TX 77030, United States
| | - James J Riviello
- Department of Pediatrics, Section of Pediatric Neurology and Developmental Neuroscience, Baylor College of Medicine, Houston, TX 77030, United States
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12
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The effects of salmon calcitonin on epileptic seizures, epileptogenesis, and postseizure hippocampal neuronal damage in pentylenetetrazole-induced epilepsy model in rats. Epilepsy Behav 2020; 113:107501. [PMID: 33220584 DOI: 10.1016/j.yebeh.2020.107501] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/09/2020] [Accepted: 09/11/2020] [Indexed: 01/04/2023]
Abstract
Epilepsy is one of the most common neurological disorders that severely affect the life quality of many people worldwide. Excitatory-inhibitory mechanisms, oxidative stress, and also inflammation systems have been implicated in the pathogenesis of epilepsy. Recent studies have shown that salmon calcitonin (sCT) has positive effects on the nervous system. However, its relation with epilepsy is still unclear. This study aimed to investigate the effect of sCT on epileptic seizures, epileptogenesis, and postseizure hippocampal neuronal damage in pentylenetetrazole (PTZ)-induced epilepsy model in rats. The study was performed in two steps. In the first step, the effect of sCT on epileptic seizures was evaluated by using electroencephalography (EEG) in fully kindled rats. In the second step, the effect of sCT on epileptogenesis was evaluated by using the kindling process. Glutamate and gamma-aminobutyric acid (GABA), thiobarbituric acid reactive substance (TBARS), superoxide dismutase (SOD), catalase (CAT), tumor necrosis factor-alpha (TNF-α), interleukin 1 beta (IL-1 β), and interleukin 6 (IL-6) were measured in the second group in the brain and serum. Hippocampal regions were stained with hematoxylin-eosin and toluidine blue to evaluate hippocampal neuronal damage histopathologically. Salmon calcitonin showed an antiepileptic effect in fully kindled rats and also prevented the development of epileptogenesis in the kindling process. Besides, sCT decreased glutamate and increased GABA levels. Furthermore, it reduced TBARS levels and increased SOD and CAT levels. On the other hand, it decreased TNF-α levels, IL-1 β levels, and IL-6 levels. Histopathologically, sCT decreased neuronal damage in all hippocampal regions. Our findings are the first preclinical report to show the positive effect of sCT on epileptic seizures and epileptogenesis. Further investigation is required to answer the questions raised about the probable mechanisms involved.
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Development and In Vivo Preclinical Imaging of Fluorine-18-Labeled Synaptic Vesicle Protein 2A (SV2A) PET Tracers. Mol Imaging Biol 2020; 21:509-518. [PMID: 30084043 DOI: 10.1007/s11307-018-1260-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PURPOSE Synaptic vesicle protein 2A (SV2A) serves as a biomarker of synaptic density and positron emission tomography (PET) imaging of SV2A could provide a tool to assess progression of neurodegenerative diseases. Two tracers have primarily been reported and characterized in vivo: [11C]UCB-J and [18F]UCB-H. In early human studies, [11C]UCB-J showed promising results, while its F-18-labeled analogue [18F]UCB-H showed suboptimal specific signal in comparison to [11C]UCB-J. Considering the limited use of [11C]UCB-J to facilities with a cyclotron, having a F-18 variant would facilitate large, multicenter imaging trials. We have screened several F-18 derivatives of UCB-J in non-human primates and identified a promising F-18 PET candidate, [18F]MNI-1126, with additional investigations of the racemate [18F]MNI-1038, affording a signal comparable to [11C]UCB-J. PROCEDURES F-18 derivatives of UCB-J and UCB-H were synthesized and administered to non-human primates for microPET imaging. Following screenings, [18F]MNI-1038 (racemate) and [18F]MNI-1126 (R-enantiomer) were identified with the highest signal and favorable kinetics and were selected for further imaging. Kinetic modeling with one- and two-tissue compartmental models, and linear methods were applied to PET data using metabolite-corrected arterial input function. Pre-block scans with levetiracetam (LEV, 10, 30 mg/kg, iv) were performed to determine the tracers' in vivo specificity for SV2A. Two whole-body PET studies were performed with [18F]MNI-1038 in one male and one female rhesus, and radiation absorbed dose estimates and effective dose (ED, ICRP-103) were estimated with OLINDA/EXM 2.0. RESULTS All compounds screened displayed very good brain penetration, with a plasma-free fraction of ~ 40 %. [18F]MNI-1126 and [18F]MNI-1038 showed uptake and distribution the most consistent with UCB-J, while the other derivatives showed suboptimal results, with similar or lower uptake than [18F]UCB-H. VT of [18F]MNI-1126 and [18F]MNI-1038 was high in all gray matter regions (within animal averages ~ 30 ml/cm3) and highly correlated with [11C]UCB-J (r > 0.99). Pre-blocking of [18F]MNI-1126 or [18F]MNI-1038 with LEV showed robust occupancy across all gray matter regions, similar to that reported with [11C]UCB-J (~ 85 % at 30 mg/kg, ~ 65 % at 10 mg/kg). Using the centrum semiovale as a reference region, BPND of [18F]MNI-1126 reached values of up to ~ 30 to 40 % higher than those reported for [11C]UCB-J. From whole-body imaging average ED of [18F]MNI-1038 was estimated to be 22.3 μSv/MBq, with tracer being eliminated via both urinary and hepatobiliary pathways. CONCLUSIONS We have identified a F-18-labeled tracer ([18F]MNI-1126) that exhibits comparable in vivo characteristics and specificity for SV2A to [11C]UCB-J in non-human primates, which makes [18F]MNI-1126 a promising PET radiotracer for imaging SV2A in human trials.
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Beauclair L, Ramé C, Arensburger P, Piégu B, Guillou F, Dupont J, Bigot Y. Sequence properties of certain GC rich avian genes, their origins and absence from genome assemblies: case studies. BMC Genomics 2019; 20:734. [PMID: 31610792 PMCID: PMC6792250 DOI: 10.1186/s12864-019-6131-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 09/23/2019] [Indexed: 12/14/2022] Open
Abstract
Background More and more eukaryotic genomes are sequenced and assembled, most of them presented as a complete model in which missing chromosomal regions are filled by Ns and where a few chromosomes may be lacking. Avian genomes often contain sequences with high GC content, which has been hypothesized to be at the origin of many missing sequences in these genomes. We investigated features of these missing sequences to discover why some may not have been integrated into genomic libraries and/or sequenced. Results The sequences of five red jungle fowl cDNA models with high GC content were used as queries to search publicly available datasets of Illumina and Pacbio sequencing reads. These were used to reconstruct the leptin, TNFα, MRPL52, PCP2 and PET100 genes, all of which are absent from the red jungle fowl genome model. These gene sequences displayed elevated GC contents, had intron sizes that were sometimes larger than non-avian orthologues, and had non-coding regions that contained numerous tandem and inverted repeat sequences with motifs able to assemble into stable G-quadruplexes and intrastrand dyadic structures. Our results suggest that Illumina technology was unable to sequence the non-coding regions of these genes. On the other hand, PacBio technology was able to sequence these regions, but with dramatically lower efficiency than would typically be expected. Conclusions High GC content was not the principal reason why numerous GC-rich regions of avian genomes are missing from genome assembly models. Instead, it is the presence of tandem repeats containing motifs capable of assembling into very stable secondary structures that is likely responsible.
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Affiliation(s)
- Linda Beauclair
- PRC, UMR INRA0085, CNRS 7247, Centre INRA Val de Loire, 37380, Nouzilly, France
| | - Christelle Ramé
- PRC, UMR INRA0085, CNRS 7247, Centre INRA Val de Loire, 37380, Nouzilly, France
| | - Peter Arensburger
- Biological Sciences Department, California State Polytechnic University, Pomona, CA, 91768, USA
| | - Benoît Piégu
- PRC, UMR INRA0085, CNRS 7247, Centre INRA Val de Loire, 37380, Nouzilly, France
| | - Florian Guillou
- PRC, UMR INRA0085, CNRS 7247, Centre INRA Val de Loire, 37380, Nouzilly, France
| | - Joëlle Dupont
- PRC, UMR INRA0085, CNRS 7247, Centre INRA Val de Loire, 37380, Nouzilly, France
| | - Yves Bigot
- PRC, UMR INRA0085, CNRS 7247, Centre INRA Val de Loire, 37380, Nouzilly, France.
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Stout KA, Dunn AR, Hoffman C, Miller GW. The Synaptic Vesicle Glycoprotein 2: Structure, Function, and Disease Relevance. ACS Chem Neurosci 2019; 10:3927-3938. [PMID: 31394034 DOI: 10.1021/acschemneuro.9b00351] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The synaptic vesicle glycoprotein 2 (SV2) family is comprised of three paralogues: SV2A, SV2B, and SV2C. In vertebrates, SV2s are 12-transmembrane proteins present on every secretory vesicle, including synaptic vesicles, and are critical to neurotransmission. Structural and functional studies suggest that SV2 proteins may play several roles to promote proper vesicular function. Among these roles are their potential to stabilize the transmitter content of vesicles, to maintain and orient the releasable pool of vesicles, and to regulate vesicular calcium sensitivity to ensure efficient, coordinated release of the transmitter. The SV2 family is highly relevant to human health in a number of ways. First, SV2A plays a role in neuronal excitability and as such is the specific target for the antiepileptic drug levetiracetam. SV2 proteins also act as the target by which potent neurotoxins, particularly botulinum, gain access to neurons and exert their toxicity. Both SV2B and SV2C are increasingly implicated in diseases such as Alzheimer's disease and Parkinson's disease. Interestingly, despite decades of intensive research, their exact function remains elusive. Thus, SV2 proteins are intriguing in their potentially diverse roles within the presynaptic terminal, and several recent developments have enhanced our understanding and appreciation of the protein family. Here, we review the structure and function of SV2 proteins as well as their relevance to disease and therapeutic development.
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Affiliation(s)
- Kristen A Stout
- Department of Physiology , Northwestern University, Feinberg School of Medicine , Chicago , Illinois , United States
| | - Amy R Dunn
- The Jackson Laboratory , Bar Harbor , Maine , United States
| | - Carlie Hoffman
- Department of Environmental Health, Rollins School of Public Health , Emory University , Atlanta , Georgia , United States
| | - Gary W Miller
- Department of Environmental Health Sciences, Mailman School of Public Health , Columbia University , New York , New York , United States
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Abstract
Reflex epilepsies (REs) are identified as epileptic seizures that are consistently induced by identifiable and objective-specific triggers, which may be an afferent stimulus or by the patient's own activity. RE may have different subtypes depending on the stimulus characteristic. There are significant clinical and electrophysiologic differences between different RE types. Visual stimuli-sensitive or photosensitive epilepsies constitute a large proportion of the RE and are mainly related to genetic causes. Reflex epilepsies may present with focal or generalized seizures due to specific triggers, and sometimes seizures may occur spontaneously. The stimuli can be external (light flashes, hot water), internal (emotion, thinking), or both and should be distinguished from triggering precipitants, which most epileptic patients could report such as emotional stress, sleep deprivation, alcohol, and menstrual cycle. Different genetic and acquired factors may play a role in etiology of RE. This review will provide a current overview of the triggering factors and management of reflex seizures.
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Affiliation(s)
| | - Çiğdem Özkara
- Department of Neurology and Clinical Neurophysiology, Cerrahpasa Faculty of Medicine, University of Istanbul, Istanbul, Turkey
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17
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Dunn AR, Hoffman CA, Stout KA, Ozawa M, Dhamsania RK, Miller GW. Immunochemical analysis of the expression of SV2C in mouse, macaque and human brain. Brain Res 2017; 1702:85-95. [PMID: 29274878 DOI: 10.1016/j.brainres.2017.12.029] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 11/30/2017] [Accepted: 12/19/2017] [Indexed: 11/17/2022]
Abstract
The synaptic vesicle glycoprotein 2C (SV2C) is an undercharacterized protein with enriched expression in phylogenetically old brain regions. Its precise role within the brain is unclear, though various lines of evidence suggest that SV2C is involved in the function of synaptic vesicles through the regulation of vesicular trafficking, calcium-induced exocytosis, or synaptotagmin function. SV2C has been linked to multiple neurological disorders, including Parkinson's disease and psychiatric conditions. SV2C is expressed in various cell types-primarily dopaminergic, GABAergic, and cholinergic cells. In mice, it is most highly expressed in nuclei within the basal ganglia, though it is unknown if this pattern of expression is consistent across species. Here, we use a custom SV2C-specific antiserum to describe localization within the brain of mouse, nonhuman primate, and human, including cell-type localization. We found that the immunoreactivity with this antiserum is consistent with previously-published antibodies, and confirmed localization of SV2C in the basal ganglia of rodent, rhesus macaque, and human. We observed strongest expression of SV2C in the substantia nigra, ventral tegmental area, dorsal striatum, pallidum, and nucleus accumbens of each species. Further, we demonstrate colocalization between SV2C and markers of dopaminergic, GABAergic, and cholinergic neurons within these brain regions. SV2C has been increasingly linked to dopamine and basal ganglia function. These antisera will be an important resource moving forward in our understanding of the role of SV2C in vesicle dynamics and neurological disease.
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Affiliation(s)
- Amy R Dunn
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Carlie A Hoffman
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Kristen A Stout
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Minagi Ozawa
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Rohan K Dhamsania
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States
| | - Gary W Miller
- Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, United States; Center for Neurodegenerative Disease, Emory University, Atlanta, GA 30322, United States.
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Amin F, Dar AH, Osama K, Khan F, Mitha R, Tharwani A, Haider G, Chand P, Arain FM. A species dependent response to the pro-epileptic drug pentylentetrazole in birds. Brain Res Bull 2017; 134:189-194. [PMID: 28802899 DOI: 10.1016/j.brainresbull.2017.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 07/19/2017] [Accepted: 08/07/2017] [Indexed: 11/18/2022]
Abstract
Epilepsy is common disorder that affects over 50 million people worldwide. Birds remain a promising yet largely under-explored model of epilepsy. This study reports the comparison of the response of two species of birds, Australian Parrots (APs) and Sparrows (SPs), to a pro-epileptic drug, Pentylenetetrazole (PTZ). PTZ injections caused myoclonic jerks (MCJs) and tonic clonic seizures (TCSs) in both species. The frequency of MCJs in APs was greater at the dose of 75mg/kg compared to both 50mg/kg and 25mg/kg while it was not significantly different in SPs. The comparison of APs and SPs showed that the frequency of MCJs was greater in APs compared to SPs at 25mg/kg and 75mg/kg while its latency was reduced at 25mg/kg and 50mg/kg. Interestingly SPs had a reduced latency of TCSs compared to APs at 75mg/kg. Glutamatergic and Gabaergic cell count was conducted to determine an association with the epileptic response to PTZ. The Glutamatergic cell counts for SPs was significantly greater than APs and conversely the Gabaergic cell counts in APs was higher compared to SPs. The reason for this difference in findings needs to be further investigated. This study shows that birds, and APs and SPs in particular, are a valid, interesting and under-explored model of epilepsy that should be further explored in order to understand the mysteries of epilepsy.
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Affiliation(s)
- Faiq Amin
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Asim H Dar
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Khan Osama
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Faezah Khan
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Rida Mitha
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Arsal Tharwani
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Ghulam Haider
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan
| | - Prem Chand
- Department of Pedeatric Neurology, The Aga Khan University, Pakistan
| | - Fazal M Arain
- Department of Biological and Biomedical Sciences, The Aga Khan University, Pakistan.
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Moseley BD, Sperling MR, Asadi-Pooya AA, Diaz A, Elmouft S, Schiemann J, Whitesides J. Efficacy, safety, and tolerability of adjunctive brivaracetam for secondarily generalized tonic-clonic seizures: Pooled results from three Phase III studies. Epilepsy Res 2016; 127:179-185. [DOI: 10.1016/j.eplepsyres.2016.09.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 08/26/2016] [Accepted: 09/01/2016] [Indexed: 12/24/2022]
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Italiano D, Striano P, Russo E, Leo A, Spina E, Zara F, Striano S, Gambardella A, Labate A, Gasparini S, Lamberti M, De Sarro G, Aguglia U, Ferlazzo E. Genetics of reflex seizures and epilepsies in humans and animals. Epilepsy Res 2016; 121:47-54. [PMID: 26875109 DOI: 10.1016/j.eplepsyres.2016.01.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 01/22/2016] [Accepted: 01/29/2016] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Reflex seizures are epileptic events triggered by specific motor, sensory or cognitive stimulation. This comprehensive narrative review focuses on the role of genetic determinants in humans and animal models of reflex seizures and epilepsies. METHODS References were mainly identified through MEDLINE searches until August 2015 and backtracking of references in pertinent studies. RESULTS Autosomal dominant inheritance with reduced penetrance was proven in several families with photosensitivity. Molecular genetic studies on EEG photoparoxysmal response identified putative loci on chromosomes 6, 7, 13 and 16 that seem to correlate with peculiar seizure phenotype. No specific mutation has been found in Papio papio baboon, although a genetic etiology is likely. Mutation in synaptic vesicle glycoprotein 2A was found in another animal model of photosensitivity (Fayoumi chickens). Autosomal dominant inheritance with incomplete penetrance overlapping with a genetic background for IGE was proposed for some families with primary reading epilepsy. Musicogenic seizures usually occur in patients with focal symptomatic or cryptogenic epilepsies, but they have been reported in rare genetic epilepsies such as Dravet syndrome. A single LGI1 mutation has been described in a girl with seizures evoked by auditory stimuli. Interestingly, heterozygous knockout (Lgi1(+/-)) mice show susceptibility to sound-triggered seizures. Moreover, in Frings and Black Swiss mice, the spontaneous mutations of MASS1 and JAMS1 genes, respectively, have been linked to audiogenic seizures. Eating seizures usually occur in symptomatic epilepsies but evidences for a genetic susceptibility were mainly provided by family report from Sri Lanka. Eating seizures were also reported in rare patients with MECP2 duplication or mutation. Hot water seizures are genetically heterogeneous but two loci at chromosomes 4 and 10 were identified in families with likely autosomal dominant inheritance. Startle-induced seizures usually occur in patients with symptomatic epilepsies but have also been reported in the setting chromosomal disorders or genetically inherited lysosomal storage diseases. DISCUSSION The genetic background of reflex seizures and epilepsies is heterogeneous and mostly unknown with no major gene identified in humans. The benefits offered by next-generation sequencing technologies should be merged with increasing information on animal models that represent an useful tool to study the mechanism underlying epileptogenesis. Finally, we expect that genetic studies will lead to a better understanding of the multiple factors involved in the pathophysiology of reflex seizures, and eventually to develop preventive strategies focused on seizure control and therapy optimization.
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Affiliation(s)
- Domenico Italiano
- Department of Clinical and Experimental Medicine, University of Messina, Via Consolare Valeria, 1, Messina, Italy
| | - Pasquale Striano
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, "G. Gaslini" Institute, Genova, Italy
| | - Emilio Russo
- Science of Health Department, School of Medicine, University of Catanzaro, Viale Europa, Catanzaro, Italy
| | - Antonio Leo
- Science of Health Department, School of Medicine, University of Catanzaro, Viale Europa, Catanzaro, Italy
| | - Edoardo Spina
- Department of Clinical and Experimental Medicine, University of Messina, Via Consolare Valeria, 1, Messina, Italy
| | - Federico Zara
- Laboratory of Neurogenetics and Neurosciences, Department of Neurosciences, "G. Gaslini" Institute, Genova, Italy
| | - Salvatore Striano
- Epilepsy Center, Department of Neurosciences, Reproductive and Odontostomatological Sciences, Federico II University, Naples, Italy
| | - Antonio Gambardella
- Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Viale Europa, Catanzaro, Italy; Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Viale Europa, Catanzaro, Italy
| | - Angelo Labate
- Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Viale Europa, Catanzaro, Italy; Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Viale Europa, Catanzaro, Italy
| | - Sara Gasparini
- Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Viale Europa, Catanzaro, Italy; Regional Epilepsy Centre, Bianchi-Melacrino-Morelli Hospital, Reggio Calabria, Italy
| | - Marco Lamberti
- Department of Clinical and Experimental Medicine, University of Messina, Via Consolare Valeria, 1, Messina, Italy
| | - Giovambattista De Sarro
- Science of Health Department, School of Medicine, University of Catanzaro, Viale Europa, Catanzaro, Italy
| | - Umberto Aguglia
- Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Viale Europa, Catanzaro, Italy; Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Viale Europa, Catanzaro, Italy; Regional Epilepsy Centre, Bianchi-Melacrino-Morelli Hospital, Reggio Calabria, Italy.
| | - Edoardo Ferlazzo
- Department of Medical and Surgical Sciences, Magna Graecia University of Catanzaro, Viale Europa, Catanzaro, Italy; Institute of Molecular Bioimaging and Physiology of the National Research Council (IBFM-CNR), Viale Europa, Catanzaro, Italy; Regional Epilepsy Centre, Bianchi-Melacrino-Morelli Hospital, Reggio Calabria, Italy
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Leroy G, Besbes B, Boettcher P, Hoffmann I, Capitan A, Baumung R. Rare phenotypes in domestic animals: unique resources for multiple applications. Anim Genet 2015; 47:141-53. [PMID: 26662214 DOI: 10.1111/age.12393] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2015] [Indexed: 12/26/2022]
Abstract
Preservation of specific and inheritable phenotypes of current or potential future importance is one of the main purposes of conservation of animal genetic resources. In this review, we investigate the issues behind the characterisation, utilisation and conservation of rare phenotypes, considering their multiple paths of relevance, variable levels of complexity and mode of inheritance. Accurately assessing the rarity of a given phenotype, especially a complex one, is not a simple task, because it requires the phenotypic and genetic characterisation of a large number of animals and populations and remains dependent of the scale of the study. Once characterised, specific phenotypes may contribute to various purposes (adaptedness, production, biological model, aesthetics, etc.) with adequate introgression programmes, which justifies the consideration of (real or potential) existence of such characteristics in in situ or ex situ conservation strategies. Recent biotechnological developments (genomic and genetic engineering) will undoubtedly bring important changes to the way phenotypes are characterised, introgressed and managed.
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Affiliation(s)
- G Leroy
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153, Rome, Italy
| | - B Besbes
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153, Rome, Italy
| | - P Boettcher
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153, Rome, Italy
| | - I Hoffmann
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153, Rome, Italy
| | - A Capitan
- INRA, UMR 1313 Génétique Animale et Biologie Intégrative, Domaine de Vilvert, F-78352, Jouy-en-Josas, France.,ALLICE, 149 rue de Bercy, F-75012, Paris, France
| | - R Baumung
- Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme di Caracalla, 00153, Rome, Italy
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Versace E, Vallortigara G. Origins of Knowledge: Insights from Precocial Species. Front Behav Neurosci 2015; 9:338. [PMID: 26696856 PMCID: PMC4673401 DOI: 10.3389/fnbeh.2015.00338] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 11/20/2015] [Indexed: 01/01/2023] Open
Abstract
Behavioral responses are influenced by knowledge acquired during the lifetime of an individual and by predispositions transmitted across generations. Establishing the origin of knowledge and the role of the unlearned component is a challenging task, given that both learned and unlearned knowledge can orient perception, learning, and the encoding of environmental features since the first stages of life. Ethical and practical issues constrain the investigation of unlearned knowledge in altricial species, including human beings. On the contrary, precocial animals can be tested on a wide range of tasks and capabilities immediately after birth and in controlled rearing conditions. Insects and precocial avian species are very convenient models to dissect the knowledge systems that enable young individuals to cope with their environment in the absence of specific previous experience. We present the state of the art of research on the origins of knowledge that comes from different models and disciplines. Insects have been mainly used to investigate unlearned sensory preferences and prepared learning mechanisms. The relative simplicity of the neural system and fast life cycle of insects make them ideal models to investigate the neural circuitry and evolutionary dynamics of unlearned traits. Among avian species, chicks of the domestic fowl have been the focus of many studies, and showed to possess unlearned knowledge in the sensory, physical, spatial, numerical and social domains. Solid evidence shows the existence of unlearned knowledge in different domains in several species, from sensory and social preferences to the left-right representation of the mental number line. We show how non-mammalian models of cognition, and in particular precocial species, can shed light into the adaptive value and evolutionary history of unlearned knowledge.
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Affiliation(s)
- Elisabetta Versace
- Animal Cognition and Neuroscience Laboratory, Center for Mind/Brain Sciences, University of Trento Rovereto, Italy
| | - Giorgio Vallortigara
- Animal Cognition and Neuroscience Laboratory, Center for Mind/Brain Sciences, University of Trento Rovereto, Italy
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Schmid M, Smith J, Burt DW, Aken BL, Antin PB, Archibald AL, Ashwell C, Blackshear PJ, Boschiero C, Brown CT, Burgess SC, Cheng HH, Chow W, Coble DJ, Cooksey A, Crooijmans RPMA, Damas J, Davis RVN, de Koning DJ, Delany ME, Derrien T, Desta TT, Dunn IC, Dunn M, Ellegren H, Eöry L, Erb I, Farré M, Fasold M, Fleming D, Flicek P, Fowler KE, Frésard L, Froman DP, Garceau V, Gardner PP, Gheyas AA, Griffin DK, Groenen MAM, Haaf T, Hanotte O, Hart A, Häsler J, Hedges SB, Hertel J, Howe K, Hubbard A, Hume DA, Kaiser P, Kedra D, Kemp SJ, Klopp C, Kniel KE, Kuo R, Lagarrigue S, Lamont SJ, Larkin DM, Lawal RA, Markland SM, McCarthy F, McCormack HA, McPherson MC, Motegi A, Muljo SA, Münsterberg A, Nag R, Nanda I, Neuberger M, Nitsche A, Notredame C, Noyes H, O'Connor R, O'Hare EA, Oler AJ, Ommeh SC, Pais H, Persia M, Pitel F, Preeyanon L, Prieto Barja P, Pritchett EM, Rhoads DD, Robinson CM, Romanov MN, Rothschild M, Roux PF, Schmidt CJ, Schneider AS, Schwartz MG, Searle SM, Skinner MA, Smith CA, Stadler PF, Steeves TE, Steinlein C, Sun L, Takata M, Ulitsky I, Wang Q, Wang Y, Warren WC, Wood JMD, Wragg D, Zhou H. Third Report on Chicken Genes and Chromosomes 2015. Cytogenet Genome Res 2015; 145:78-179. [PMID: 26282327 PMCID: PMC5120589 DOI: 10.1159/000430927] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Michael Schmid
- Department of Human Genetics, University of Würzburg, Würzburg, Germany
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Homozygous Mutation in Synaptic Vesicle Glycoprotein 2A Gene Results in Intractable Epilepsy, Involuntary Movements, Microcephaly, and Developmental and Growth Retardation. Pediatr Neurol 2015; 52:642-6.e1. [PMID: 26002053 DOI: 10.1016/j.pediatrneurol.2015.02.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/06/2015] [Accepted: 02/11/2015] [Indexed: 11/23/2022]
Abstract
BACKGROUND Synaptic vesicle protein 2A (SV2a) is the binding site of the antiepileptic drug levetiracetam and the only known synaptic vesicle target of an epilepsy medication. To date, no pathogenic mutation in SV2A, which is the gene encoding synaptic vesicle glycoprotein 2A, has been identified in humans. We report a homozygous mutation in the SV2A gene in a patient with intractable epilepsy. METHODS We investigated a patient with intractable epilepsy, involuntary movements, microcephaly, and developmental and growth retardation. Both parents were multiply consanguineous and an earlier-born brother of the proband had a similar course and died at 7 months of age. Detailed clinical history, imaging, electroencephalograph and metabolic testing were obtained. Full exome sequencing was performed using genomic DNA isolated from the patient and both parents. RESULTS Exome sequencing identified a homozygous arginine to glutamine mutation in amino acid position 383 (R383Q) in exon 5 of the SV2A gene. Both parents were carriers for the R383Q variant, suggesting that R383Q is a recessive mutation. There were no other candidate alterations in the exome that could explain the phenotype in the proband. The amino acid arginine at position 383 of SV2a gene is evolutionally conserved throughout vertebrates. R383Q change is not observed in known healthy cohorts, exome databases, or the Database of Single Nucleotide Polymorphisms. The R383Q mutation is located in the second adenine binding domain in SV2a protein and may alter adenine nucleotides binding to SV2a. CONCLUSION Our report provides the elusive evidence that an SV2A mutation can be a cause of epilepsy in humans. Levetiracetam, which binds to SV2A, was not effective as an antiepileptic medication. The location of the mutation in our patient supports an important role of adenine nucleotides binding in SV2A function.
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Hippocampal low-frequency stimulation increased SV2A expression and inhibited the seizure degree in pharmacoresistant amygdala-kindling epileptic rats. Epilepsy Res 2014; 108:1483-91. [DOI: 10.1016/j.eplepsyres.2014.07.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 07/21/2014] [Accepted: 07/27/2014] [Indexed: 11/19/2022]
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Mendoza-Torreblanca JG, Vanoye-Carlo A, Phillips-Farfán BV, Carmona-Aparicio L, Gómez-Lira G. Synaptic vesicle protein 2A: basic facts and role in synaptic function. Eur J Neurosci 2013; 38:3529-39. [DOI: 10.1111/ejn.12360] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 08/09/2013] [Accepted: 08/17/2013] [Indexed: 10/26/2022]
Affiliation(s)
| | | | | | | | - Gisela Gómez-Lira
- Department of Pharmacobiology; Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional; Calzada de los Tenorios 235 Col. Granjas Coapa C.P. 14330 D. F., Mexico
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Woods JO, Singh-Blom UM, Laurent JM, McGary KL, Marcotte EM. Prediction of gene-phenotype associations in humans, mice, and plants using phenologs. BMC Bioinformatics 2013; 14:203. [PMID: 23800157 PMCID: PMC3704650 DOI: 10.1186/1471-2105-14-203] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 05/24/2013] [Indexed: 12/19/2022] Open
Abstract
Background Phenotypes and diseases may be related to seemingly dissimilar phenotypes in other species by means of the orthology of underlying genes. Such “orthologous phenotypes,” or “phenologs,” are examples of deep homology, and may be used to predict additional candidate disease genes. Results In this work, we develop an unsupervised algorithm for ranking phenolog-based candidate disease genes through the integration of predictions from the k nearest neighbor phenologs, comparing classifiers and weighting functions by cross-validation. We also improve upon the original method by extending the theory to paralogous phenotypes. Our algorithm makes use of additional phenotype data — from chicken, zebrafish, and E. coli, as well as new datasets for C. elegans — establishing that several types of annotations may be treated as phenotypes. We demonstrate the use of our algorithm to predict novel candidate genes for human atrial fibrillation (such as HRH2, ATP4A, ATP4B, and HOPX) and epilepsy (e.g., PAX6 and NKX2-1). We suggest gene candidates for pharmacologically-induced seizures in mouse, solely based on orthologous phenotypes from E. coli. We also explore the prediction of plant gene–phenotype associations, as for the Arabidopsis response to vernalization phenotype. Conclusions We are able to rank gene predictions for a significant portion of the diseases in the Online Mendelian Inheritance in Man database. Additionally, our method suggests candidate genes for mammalian seizures based only on bacterial phenotypes and gene orthology. We demonstrate that phenotype information may come from diverse sources, including drug sensitivities, gene ontology biological processes, and in situ hybridization annotations. Finally, we offer testable candidates for a variety of human diseases, plant traits, and other classes of phenotypes across a wide array of species.
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Affiliation(s)
- John O Woods
- Center for Systems & Synthetic Biology, Institute for Cellular & Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA
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