1
|
Pinheiro-Junior EL, Alirahimi E, Peigneur S, Isensee J, Schiffmann S, Erkoc P, Fürst R, Vilcinskas A, Sennoner T, Koludarov I, Hempel BF, Tytgat J, Hucho T, von Reumont BM. Diversely evolved xibalbin variants from remipede venom inhibit potassium channels and activate PKA-II and Erk1/2 signaling. BMC Biol 2024; 22:164. [PMID: 39075558 PMCID: PMC11288129 DOI: 10.1186/s12915-024-01955-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Accepted: 07/09/2024] [Indexed: 07/31/2024] Open
Abstract
BACKGROUND The identification of novel toxins from overlooked and taxonomically exceptional species bears potential for various pharmacological applications. The remipede Xibalbanus tulumensis, an underwater cave-dwelling crustacean, is the only crustacean for which a venom system has been described. Its venom contains several xibalbin peptides that have an inhibitor cysteine knot (ICK) scaffold. RESULTS Our screenings revealed that all tested xibalbin variants particularly inhibit potassium channels. Xib1 and xib13 with their eight-cysteine domain similar to spider knottins also inhibit voltage-gated sodium channels. No activity was noted on calcium channels. Expanding the functional testing, we demonstrate that xib1 and xib13 increase PKA-II and Erk1/2 sensitization signaling in nociceptive neurons, which may initiate pain sensitization. Our phylogenetic analysis suggests that xib13 either originates from the common ancestor of pancrustaceans or earlier while xib1 is more restricted to remipedes. The ten-cysteine scaffolded xib2 emerged from xib1, a result that is supported by our phylogenetic and machine learning-based analyses. CONCLUSIONS Our functional characterization of synthesized variants of xib1, xib2, and xib13 elucidates their potential as inhibitors of potassium channels in mammalian systems. The specific interaction of xib2 with Kv1.6 channels, which are relevant to treating variants of epilepsy, shows potential for further studies. At higher concentrations, xib1 and xib13 activate the kinases PKA-II and ERK1/2 in mammalian sensory neurons, suggesting pain sensitization and potential applications related to pain research and therapy. While tested insect channels suggest that all probably act as neurotoxins, the biological function of xib1, xib2, and xib13 requires further elucidation. A novel finding on their evolutionary origin is the apparent emergence of X. tulumensis-specific xib2 from xib1. Our study is an important cornerstone for future studies to untangle the origin and function of these enigmatic proteins as important components of remipede but also other pancrustacean and arthropod venoms.
Collapse
Affiliation(s)
- Ernesto Lopes Pinheiro-Junior
- Toxicology and Pharmacology - Campus Gasthuisberg, University of Leuven (KU Leuven), Herestraat 49, PO Box 922, 3000, Louvain, Belgium
| | - Ehsan Alirahimi
- Department of Anesthesiology and Intensive Care Medicine, University Cologne, Translational Pain Research, University Hospital of Cologne, Cologne, Germany
| | - Steve Peigneur
- Toxicology and Pharmacology - Campus Gasthuisberg, University of Leuven (KU Leuven), Herestraat 49, PO Box 922, 3000, Louvain, Belgium
| | - Jörg Isensee
- Department of Anesthesiology and Intensive Care Medicine, University Cologne, Translational Pain Research, University Hospital of Cologne, Cologne, Germany
| | - Susanne Schiffmann
- Fraunhofer Institute for Translational Medicine and Pharmacology ITMP, Theodor-Stern-Kai 7, 60596, Frankfurt Am Main, Germany
| | - Pelin Erkoc
- Institute of Pharmaceutical Biology, Goethe University Frankfurt, Max-Von-Laue-Str. 9, 60438, Frankfurt, Germany
- LOEWE Center for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany
| | - Robert Fürst
- Institute of Pharmaceutical Biology, Goethe University Frankfurt, Max-Von-Laue-Str. 9, 60438, Frankfurt, Germany
- LOEWE Center for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany
| | - Andreas Vilcinskas
- LOEWE Center for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany
- Department of Bioresources, Fraunhofer Institute for Molecular Biology and Applied Ecology (IME-BR), Ohlebergsweg 14, 35394, Giessen, Germany
| | - Tobias Sennoner
- Department of Informatics, Bioinformatics and Computational Biology, i12, Technical University of Munich, Boltzmannstr. 3, 85748, Garching, Munich, Germany
| | - Ivan Koludarov
- Department of Informatics, Bioinformatics and Computational Biology, i12, Technical University of Munich, Boltzmannstr. 3, 85748, Garching, Munich, Germany
| | - Benjamin-Florian Hempel
- Freie Unveristät Berlin, Veterinary Centre for Resistance Research (TZR), Robert-Von-Ostertag Str. 8, 14163, Berlin, Germany
| | - Jan Tytgat
- Toxicology and Pharmacology - Campus Gasthuisberg, University of Leuven (KU Leuven), Herestraat 49, PO Box 922, 3000, Louvain, Belgium
| | - Tim Hucho
- Department of Anesthesiology and Intensive Care Medicine, University Cologne, Translational Pain Research, University Hospital of Cologne, Cologne, Germany
| | - Björn M von Reumont
- LOEWE Center for Translational Biodiversity Genomics (LOEWE-TBG), Senckenberganlage 25, 60325, Frankfurt, Germany.
- Faculty of Biological Sciences, Institute of Cell Biology and Neuroscience, Goethe, Frankfurt, Max-Von-Laue-Str 13, 60438, Frankfurt, Germany.
| |
Collapse
|
2
|
Shin HJ, Ko A, Kim SH, Lee JS, Kang HC. Unusual Voltage-Gated Sodium and Potassium Channelopathies Related to Epilepsy. J Clin Neurol 2024; 20:402-411. [PMID: 38951973 PMCID: PMC11220354 DOI: 10.3988/jcn.2023.0435] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/03/2024] [Accepted: 01/23/2024] [Indexed: 07/03/2024] Open
Abstract
BACKGROUND AND PURPOSE There is extensive literature on monogenic epilepsies caused by mutations in familiar channelopathy genes such as SCN1A. However, information on other less-common channelopathy genes is scarce. This study aimed to explore the genetic and clinical characteristics of patients diagnosed with unusual voltage-gated sodium and potassium channelopathies related to epilepsy. METHODS This observational, retrospective study analyzed pediatric patients with epilepsy who carried pathogenic variants of unusual voltage-gated sodium and potassium channelopathy genes responsible for seizure-associated phenotypes. Targeted next-generation sequencing (NGS) panel tests were performed between November 2016 and June 2022 at Severance Children's Hospital, Seoul, South Korea. Clinical characteristics and the treatment responses to different types of antiseizure medications were further analyzed according to different types of gene mutation. RESULTS This study included 15 patients with the following unusual voltage-gated sodium and potassium channelopathy genes: SCN3A (n=1), SCN4A (n=1), KCNA1 (n=1), KCNA2 (n=4), KCNB1 (n=6), KCNC1 (n=1), and KCNMA1 (n=1). NGS-based genetic testing identified 13 missense mutations (87%), 1 splice-site variant (7%), and 1 copy-number variant (7%). Developmental and epileptic encephalopathy was diagnosed in nine (60%) patients. Seizure freedom was eventually achieved in eight (53%) patients, whereas seizures persisted in seven (47%) patients. CONCLUSIONS Our findings broaden the genotypic and phenotypic spectra of less-common voltage-gated sodium and potassium channelopathies associated with epilepsy.
Collapse
Affiliation(s)
- Hui Jin Shin
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Ara Ko
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Se Hee Kim
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Joon Soo Lee
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Hoon-Chul Kang
- Division of Pediatric Neurology, Department of Pediatrics, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
| |
Collapse
|
3
|
Zimmern V, Minassian B. Progressive Myoclonus Epilepsy: A Scoping Review of Diagnostic, Phenotypic and Therapeutic Advances. Genes (Basel) 2024; 15:171. [PMID: 38397161 PMCID: PMC10888128 DOI: 10.3390/genes15020171] [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: 01/02/2024] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
The progressive myoclonus epilepsies (PME) are a diverse group of disorders that feature both myoclonus and seizures that worsen gradually over a variable timeframe. While each of the disorders is individually rare, they collectively make up a non-trivial portion of the complex epilepsy and myoclonus cases that are seen in tertiary care centers. The last decade has seen substantial progress in our understanding of the pathophysiology, diagnosis, prognosis, and, in select disorders, therapies of these diseases. In this scoping review, we examine English language publications from the past decade that address diagnostic, phenotypic, and therapeutic advances in all PMEs. We then highlight the major lessons that have been learned and point out avenues for future investigation that seem promising.
Collapse
Affiliation(s)
- Vincent Zimmern
- Division of Child Neurology, University of Texas Southwestern, Dallas, TX 75390, USA;
| | | |
Collapse
|
4
|
Clatot J, Currin CB, Liang Q, Pipatpolkai T, Massey SL, Helbig I, Delemotte L, Vogels TP, Covarrubias M, Goldberg EM. A structurally precise mechanism links an epilepsy-associated KCNC2 potassium channel mutation to interneuron dysfunction. Proc Natl Acad Sci U S A 2024; 121:e2307776121. [PMID: 38194456 PMCID: PMC10801864 DOI: 10.1073/pnas.2307776121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 11/17/2023] [Indexed: 01/11/2024] Open
Abstract
De novo heterozygous variants in KCNC2 encoding the voltage-gated potassium (K+) channel subunit Kv3.2 are a recently described cause of developmental and epileptic encephalopathy (DEE). A de novo variant in KCNC2 c.374G > A (p.Cys125Tyr) was identified via exome sequencing in a patient with DEE. Relative to wild-type Kv3.2, Kv3.2-p.Cys125Tyr induces K+ currents exhibiting a large hyperpolarizing shift in the voltage dependence of activation, accelerated activation, and delayed deactivation consistent with a relative stabilization of the open conformation, along with increased current density. Leveraging the cryogenic electron microscopy (cryo-EM) structure of Kv3.1, molecular dynamic simulations suggest that a strong π-π stacking interaction between the variant Tyr125 and Tyr156 in the α-6 helix of the T1 domain promotes a relative stabilization of the open conformation of the channel, which underlies the observed gain of function. A multicompartment computational model of a Kv3-expressing parvalbumin-positive cerebral cortex fast-spiking γ-aminobutyric acidergic (GABAergic) interneuron (PV-IN) demonstrates how the Kv3.2-Cys125Tyr variant impairs neuronal excitability and dysregulates inhibition in cerebral cortex circuits to explain the resulting epilepsy.
Collapse
Affiliation(s)
- Jerome Clatot
- Division of Neurology, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
- The Epilepsy Neurogenetics Initiative, The Children’s Hospital of Philadelphia, Philadelphia,PA19104
| | | | - Qiansheng Liang
- Department of Neuroscience and Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA19107
| | - Tanadet Pipatpolkai
- Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, SolnaSE-171 21, Sweden
| | - Shavonne L. Massey
- Division of Neurology, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
- The Epilepsy Neurogenetics Initiative, The Children’s Hospital of Philadelphia, Philadelphia,PA19104
- The Department of Neurology, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA19104
| | - Ingo Helbig
- Division of Neurology, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
- The Epilepsy Neurogenetics Initiative, The Children’s Hospital of Philadelphia, Philadelphia,PA19104
- The Department of Neurology, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA19104
- Department of Biomedical and Health Informatics, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
| | - Lucie Delemotte
- Department of Applied Physics, Science for Life Laboratory, Royal Institute of Technology, SolnaSE-171 21, Sweden
| | - Tim P. Vogels
- The Institute of Science and Technology Austria, Klosterneuburg3400, Austria
| | - Manuel Covarrubias
- Department of Neuroscience and Vickie and Jack Farber Institute for Neuroscience, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA19107
| | - Ethan M. Goldberg
- Division of Neurology, The Children’s Hospital of Philadelphia, Philadelphia, PA19104
- The Epilepsy Neurogenetics Initiative, The Children’s Hospital of Philadelphia, Philadelphia,PA19104
- The Department of Neurology, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA19104
- The Department of Neuroscience, The University of Pennsylvania Perelman School of Medicine, Philadelphia, PA19104
| |
Collapse
|