1
|
Guo R, Guo G, Wang A, Xu G, Lai R, Jin H. Spider-Venom Peptides: Structure, Bioactivity, Strategy, and Research Applications. Molecules 2023; 29:35. [PMID: 38202621 PMCID: PMC10779620 DOI: 10.3390/molecules29010035] [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: 10/16/2023] [Revised: 11/30/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024] Open
Abstract
Spiders (Araneae), having thrived for over 300 million years, exhibit remarkable diversity, with 47,000 described species and an estimated 150,000 species in existence. Evolving with intricate venom, spiders are nature's skilled predators. While only a small fraction of spiders pose a threat to humans, their venoms contain complex compounds, holding promise as drug leads. Spider venoms primarily serve to immobilize prey, achieved through neurotoxins targeting ion channels. Peptides constitute a major part of these venoms, displaying diverse pharmacological activities, and making them appealing for drug development. Moreover, spider-venom peptides have emerged as valuable tools for exploring human disease mechanisms. This review focuses on the roles of spider-venom peptides in spider survival strategies and their dual significance as pharmaceutical research tools. By integrating recent discoveries, it provides a comprehensive overview of these peptides, their targets, bioactivities, and their relevance in spider survival and medical research.
Collapse
Affiliation(s)
- Ruiyin Guo
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (R.G.)
| | - Gang Guo
- The Third Affiliated Hospital of Kunming Medical University (Yunnan Cancer Hospital), Kunming 650118, China;
| | - Aili Wang
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (R.G.)
| | - Gaochi Xu
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (R.G.)
| | - Ren Lai
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (R.G.)
- Key Laboratory of Bioactive Peptides of Yunnan Province, KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases, National Resource Center for Non-Human Primates, Kunming-Primate Research Center, National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Sino-African Joint Research Center and Engineering Laboratory of Peptides, Kunming Institute of Zoology, Kunming 650107, China
| | - Hui Jin
- Center for Evolution and Conservation Biology, Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China; (R.G.)
| |
Collapse
|
2
|
Borrego J, Feher A, Jost N, Panyi G, Varga Z, Papp F. Peptide Inhibitors of Kv1.5: An Option for the Treatment of Atrial Fibrillation. Pharmaceuticals (Basel) 2021; 14:1303. [PMID: 34959701 PMCID: PMC8704205 DOI: 10.3390/ph14121303] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 12/12/2022] Open
Abstract
The human voltage gated potassium channel Kv1.5 that conducts the IKur current is a key determinant of the atrial action potential. Its mutations have been linked to hereditary forms of atrial fibrillation (AF), and the channel is an attractive target for the management of AF. The development of IKur blockers to treat AF resulted in small molecule Kv1.5 inhibitors. The selectivity of the blocker for the target channel plays an important role in the potential therapeutic application of the drug candidate: the higher the selectivity, the lower the risk of side effects. In this respect, small molecule inhibitors of Kv1.5 are compromised due to their limited selectivity. A wide range of peptide toxins from venomous animals are targeting ion channels, including mammalian channels. These peptides usually have a much larger interacting surface with the ion channel compared to small molecule inhibitors and thus, generally confer higher selectivity to the peptide blockers. We found two peptides in the literature, which inhibited IKur: Ts6 and Osu1. Their affinity and selectivity for Kv1.5 can be improved by rational drug design in which their amino acid sequences could be modified in a targeted way guided by in silico docking experiments.
Collapse
Affiliation(s)
- Jesús Borrego
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Egyetem ter 1, H-4032 Debrecen, Hungary; (J.B.); (A.F.); (G.P.); (Z.V.)
| | - Adam Feher
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Egyetem ter 1, H-4032 Debrecen, Hungary; (J.B.); (A.F.); (G.P.); (Z.V.)
| | - Norbert Jost
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, 6725 Szeged, Hungary;
- Department of Pharmacology and Pharmacotherapy, Interdisciplinary Excellence Centre, University of Szeged, 6725 Szeged, Hungary
- ELKH-SZTE Research Group for Cardiovascular Pharmacology, Eötvös Loránd Research Network, 6725 Szeged, Hungary
| | - Gyorgy Panyi
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Egyetem ter 1, H-4032 Debrecen, Hungary; (J.B.); (A.F.); (G.P.); (Z.V.)
| | - Zoltan Varga
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Egyetem ter 1, H-4032 Debrecen, Hungary; (J.B.); (A.F.); (G.P.); (Z.V.)
| | - Ferenc Papp
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Egyetem ter 1, H-4032 Debrecen, Hungary; (J.B.); (A.F.); (G.P.); (Z.V.)
| |
Collapse
|
3
|
Macedo KWR, Costa LJDL, de Souza JO, de Vasconcelos IA, de Castro JS, de Santana CJC, Magalhães ACM, Castro MDS, Pires OR. Brazilian Theraphosidae: a toxicological point of view. J Venom Anim Toxins Incl Trop Dis 2021; 27:e20210004. [PMID: 34868282 PMCID: PMC8610171 DOI: 10.1590/1678-9199-jvatitd-2021-0004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 04/08/2021] [Indexed: 11/30/2022] Open
Abstract
The Theraphosidae family includes the largest number of species of the
Mygalomorphae infraorder, with hundreds of species currently catalogued.
However, there is a huge lack on physiologic and even ecologic information
available, especially in Brazil, which is the most biodiverse country in the
world. Over the years, spiders have been presented as a source of multiple
biologically active compounds with basic roles, such as primary defense against
pathogenic microorganisms or modulation of metabolic pathways and as specialized
hunters. Spider venoms also evolved in order to enable the capture of prey by
interaction with a diversity of molecular targets of interest, raising their
pharmaceutical potential for the development of new drugs. Among the activities
found in compounds isolated from venoms and hemocytes of Brazilian Theraphosidae
there are antimicrobial, antifungal, antiparasitic and antitumoral, as well as
properties related to proteinase action and neuromuscular blockage modulated by
ionic voltage-gated channel interaction. These characteristics are present in
different species from multiple genera, which is strong evidence of the
important role in spider survival. The present review aims to compile the main
results of studies from the last decades on Brazilian Theraphosidae with special
focus on results obtained with the crude venom or compounds isolated from both
venom and hemocytes, and their physiological and chemical characterization.
Collapse
Affiliation(s)
- Keven Wender Rodrigues Macedo
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Lucas Jeferson de Lima Costa
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Jéssica Oliveira de Souza
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Isadora Alves de Vasconcelos
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Jessica Schneider de Castro
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Carlos José Correia de Santana
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil.,Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Ana Carolina Martins Magalhães
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Mariana de Souza Castro
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil.,Laboratory of Biochemistry and Protein Chemistry, Department of Cell Biology, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| | - Osmindo Rodrigues Pires
- Laboratory of Toxinology, Department of Physiological Sciences, Institute of Biology, University of Brasília (UnB), Brasília, DF, Brazil
| |
Collapse
|
4
|
Zhang Y, Tachtsidis G, Schob C, Koko M, Hedrich UBS, Lerche H, Lemke JR, Haeringen A, Ruivenkamp C, Prescott T, Tveten K, Gerstner T, Pruniski B, DiTroia S, VanNoy GE, Rehm HL, McLaughlin H, Bolz HJ, Zechner U, Bryant E, McDonough T, Kindler S, Bähring R. KCND2 variants associated with global developmental delay differentially impair Kv4.2 channel gating. Hum Mol Genet 2021; 30:2300-2314. [PMID: 34245260 DOI: 10.1093/hmg/ddab192] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 07/06/2021] [Accepted: 07/07/2021] [Indexed: 11/13/2022] Open
Abstract
Here, we report on six unrelated individuals, all presenting with early-onset global developmental delay, associated with impaired motor, speech and cognitive development, partly with developmental epileptic encephalopathy and physical dysmorphisms. All individuals carry heterozygous missense variants of KCND2, which encodes the voltage-gated potassium (Kv) channel α-subunit Kv4.2. The amino acid substitutions associated with the variants, p.(Glu323Lys) (E323K), p.(Pro403Ala) (P403A), p.(Val404Leu) (V404L) and p.(Val404Met) (V404M), affect sites known to be critical for channel gating. To unravel their likely pathogenicity, recombinant mutant channels were studied in the absence and presence of auxiliary β-subunits under two-electrode voltage-clamp in Xenopus oocytes. All channel mutants exhibited slowed and incomplete macroscopic inactivation, and the P403A variant in addition slowed activation. Co-expression of KChIP2 or DPP6 augmented the functional expression of both wild-type and mutant channels, however, the auxiliary β-subunit-mediated gating modifications differed from wild-type and among mutants. To simulate the putative setting in the affected individuals, heteromeric Kv4.2 channels (wild-type + mutant) were studied as ternary complexes (containing both KChIP2 and DPP6). In the heteromeric ternary configuration, the E323K variant exhibited only marginal functional alterations compared to homomeric wild-type ternary, compatible with mild loss-of-function. By contrast, the P403A, V404L and V404M variants displayed strong gating impairment in the heteromeric ternary configuration, compatible with loss or gain-of-function. Our results support the etiological involvement of Kv4.2 channel gating impairment in early-onset monogenic global developmental delay. In addition, they suggest that gain-of-function mechanisms associated with a substitution of V404 increase epileptic seizure susceptibility.
Collapse
Affiliation(s)
- Yongqiang Zhang
- Institute for Cellular and Integrative Physiology, Center for Experimental Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany.,Southeast University, Nanjing, China
| | - Georgios Tachtsidis
- Institute for Cellular and Integrative Physiology, Center for Experimental Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Claudia Schob
- Institute for Human Genetics, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Mahmoud Koko
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, Tübingen, Germany
| | - Ulrike B S Hedrich
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, Tübingen, Germany
| | - Holger Lerche
- Department of Neurology and Epileptology, Hertie-Institute for Clinical Brain Research, Tübingen, Germany
| | - Johannes R Lemke
- University Center for Rare Diseases, Institute for Human Genetics, University Hospital, Leipzig, Germany
| | - Arie Haeringen
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Claudia Ruivenkamp
- Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Trine Prescott
- Department of Medical Genetics, Telemark Hospital Trust, Skien, Norway
| | - Kristian Tveten
- Department of Medical Genetics, Telemark Hospital Trust, Skien, Norway
| | - Thorsten Gerstner
- Department of Child Neurology and Rehabilitation and Department of Pediatrics, Hospital of Southern Norway, Arendal, Norway
| | - Brianna Pruniski
- Division of Genetics & Metabolism, Phoenix Children's Medical Group, Phoenix, AZ, USA
| | - Stephanie DiTroia
- Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Grace E VanNoy
- Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Heidi L Rehm
- Center for Mendelian Genomics and Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | | | - Hanno J Bolz
- Senckenberg Centre for Human Genetics, Frankfurt/Main, Germany.,Institute of Human Genetics, University Hospital of Cologne, Cologne, Germany
| | - Ulrich Zechner
- Senckenberg Centre for Human Genetics, Frankfurt/Main, Germany.,Institute of Human Genetics, University Medical Center Mainz, Mainz, Germany
| | - Emily Bryant
- Ann & Robert H Lurie Children's Hospital of Chicago, Department of Pediatrics, Northwestern University Feinberg Scool of Medicine, Chicago, IL, USA
| | - Tiffani McDonough
- Ann & Robert H Lurie Children's Hospital of Chicago, Department of Pediatrics, Northwestern University Feinberg Scool of Medicine, Chicago, IL, USA
| | - Stefan Kindler
- Institute for Human Genetics, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Robert Bähring
- Institute for Cellular and Integrative Physiology, Center for Experimental Medicine, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
5
|
Matsumura K, Yokogawa M, Osawa M. Peptide Toxins Targeting KV Channels. Handb Exp Pharmacol 2021; 267:481-505. [PMID: 34117930 DOI: 10.1007/164_2021_500] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
A number of peptide toxins isolated from animals target potassium ion (K+) channels. Many of them are particularly known to inhibit voltage-gated K+ (KV) channels and are mainly classified into pore-blocking toxins or gating-modifier toxins. Pore-blocking toxins directly bind to the ion permeation pores of KV channels, thereby physically occluding them. In contrast, gating-modifier toxins bind to the voltage-sensor domains of KV channels, modulating their voltage-dependent conformational changes. These peptide toxins are useful molecular tools in revealing the structure-function relationship of KV channels and have potential for novel treatments for diseases related to KV channels. This review focuses on the inhibition mechanism of pore-blocking and gating-modifier toxins that target KV channels.
Collapse
Affiliation(s)
- Kazuki Matsumura
- Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
| | - Mariko Yokogawa
- Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan
| | - Masanori Osawa
- Graduate School of Pharmaceutical Sciences, Keio University, Tokyo, Japan.
| |
Collapse
|
6
|
Cardoso FC, Castro J, Grundy L, Schober G, Garcia-Caraballo S, Zhao T, Herzig V, King GF, Brierley SM, Lewis RJ. A spider-venom peptide with multitarget activity on sodium and calcium channels alleviates chronic visceral pain in a model of irritable bowel syndrome. Pain 2021; 162:569-581. [PMID: 32826759 DOI: 10.1097/j.pain.0000000000002041] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 08/04/2020] [Indexed: 12/19/2022]
Abstract
ABSTRACT Chronic pain is a serious debilitating condition that affects ∼20% of the world's population. Currently available drugs fail to produce effective pain relief in many patients and have dose-limiting side effects. Several voltage-gated sodium (NaV) and calcium (CaV) channels are implicated in the etiology of chronic pain, particularly NaV1.1, NaV1.3, NaV1.7-NaV1.9, CaV2.2, and CaV3.2. Numerous NaV and CaV modulators have been described, but with few exceptions, they display poor potency and/or selectivity for pain-related channel subtypes. Here, we report the discovery and characterization of 2 novel tarantula-venom peptides (Tap1a and Tap2a) isolated from Theraphosa apophysis venom that modulate the activity of both NaV and CaV3 channels. Tap1a and Tap2a inhibited on-target NaV and CaV3 channels at nanomolar to micromolar concentrations and displayed moderate off-target selectivity for NaV1.6 and weak affinity for NaV1.4 and NaV1.5. The most potent inhibitor, Tap1a, nearly ablated neuronal mechanosensitivity in afferent fibers innervating the colon and the bladder, with in vivo intracolonic administration reversing colonic mechanical hypersensitivity in a mouse model of irritable bowel syndrome. These findings suggest that targeting a specific combination of NaV and CaV3 subtypes provides a novel route for treatment of chronic visceral pain.
Collapse
Affiliation(s)
- Fernanda C Cardoso
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
| | - Joel Castro
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia, Australia
| | - Luke Grundy
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia, Australia
| | - Gudrun Schober
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia, Australia
| | - Sonia Garcia-Caraballo
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia, Australia
| | - Tianjiao Zhao
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
| | - Volker Herzig
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
- School of Science and Engineering, University of the Sunshine Coast, Sippy Downs, Queensland, Australia
| | - Glenn F King
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
| | - Stuart M Brierley
- Visceral Pain Research Group, College of Medicine and Public Health, Flinders Health and Medical Research Institute, Flinders University, South Australia, Australia
- Hopwood Centre for Neurobiology, Lifelong Health Theme, South Australian Health and Medical Research Institute (SAHMRI), North Terrace, Adelaide, South Australia, Australia
| | - Richard J Lewis
- Centre for Pain Research, Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland, Australia
| |
Collapse
|
7
|
Mechanism of hERG inhibition by gating-modifier toxin, APETx1, deduced by functional characterization. BMC Mol Cell Biol 2021; 22:3. [PMID: 33413079 PMCID: PMC7791793 DOI: 10.1186/s12860-020-00337-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 12/14/2020] [Indexed: 12/13/2022] Open
Abstract
Background Human ether-à-go-go-related gene potassium channel 1 (hERG) is a voltage-gated potassium channel, the voltage-sensing domain (VSD) of which is targeted by a gating-modifier toxin, APETx1. APETx1 is a 42-residue peptide toxin of sea anemone Anthopleura elegantissima and inhibits hERG by stabilizing the resting state. A previous study that conducted cysteine-scanning analysis of hERG identified two residues in the S3-S4 region of the VSD that play important roles in hERG inhibition by APETx1. However, mutational analysis of APETx1 could not be conducted as only natural resources have been available until now. Therefore, it remains unclear where and how APETx1 interacts with the VSD in the resting state. Results We established a method for preparing recombinant APETx1 and determined the NMR structure of the recombinant APETx1, which is structurally equivalent to the natural product. Electrophysiological analyses using wild type and mutants of APETx1 and hERG revealed that their hydrophobic residues, F15, Y32, F33, and L34, in APETx1, and F508 and I521 in hERG, in addition to a previously reported acidic hERG residue, E518, play key roles in the inhibition of hERG by APETx1. Our hypothetical docking models of the APETx1-VSD complex satisfied the results of mutational analysis. Conclusions The present study identified the key residues of APETx1 and hERG that are involved in hERG inhibition by APETx1. These results would help advance understanding of the inhibitory mechanism of APETx1, which could provide a structural basis for designing novel ligands targeting the VSDs of KV channels.
Collapse
|
8
|
Kodirov SA. Tale of tail current. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 150:78-97. [PMID: 31238048 DOI: 10.1016/j.pbiomolbio.2019.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/22/2019] [Accepted: 06/20/2019] [Indexed: 02/07/2023]
Abstract
The largest biomass of channel proteins is located in unicellular organisms and bacteria that have no organs. However, orchestrated bidirectional ionic currents across the cell membrane via the channels are important for the functioning of organs of organisms, and equally concern both fauna or flora. Several ion channels are activated in the course of action potentials. One of the hallmarks of voltage-dependent channels is a 'tail current' - deactivation as observed after prior and sufficient activation predominantly at more depolarized potentials e.g. for Kv while upon hyperpolarization for HCN α subunits. Tail current also reflects the timing of channel closure that is initiated upon termination of stimuli. Finally, deactivation of currents during repolarization could be a selective estimate for given channel as in case of HERG, if dedicated long and more depolarized 'tail pulse' is used. Since from a holding potential of e.g. -70 mV are often a family of outward K+ currents comprising IA and IK are simultaneously activated in native cells.
Collapse
Affiliation(s)
- Sodikdjon A Kodirov
- Pavlov Institute of Physiology, Russian Academy of Sciences, Saint Petersburg, Russia; Cardiovascular Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA; Almazov Federal Heart, Blood and Endocrinology Centre, Saint Petersburg, 197341, Russia; Institute of Experimental Medicine, I. P. Pavlov Department of Physiology, Russian Academy of Medical Sciences, Saint Petersburg, Russia; Laboratory of Emotions' Neurobiology, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093, Poland.
| |
Collapse
|
9
|
Zhang Y, Luo J, He J, Rong M, Zeng X. JZTX-V Targets the Voltage Sensor in Kv4.2 to Inhibit I to Potassium Channels in Cardiomyocytes. Front Pharmacol 2019; 10:357. [PMID: 31040778 PMCID: PMC6476928 DOI: 10.3389/fphar.2019.00357] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 03/21/2019] [Indexed: 12/16/2022] Open
Abstract
Kv4 potassium channels are responsible for transient outward K+ currents in the cardiac action potential (AP). Previous experiments by our group demonstrated that Jingzhaotoxin-V (JZTX-V) selectively inhibits A-type potassium channels. However, the specific effects of JZTX-V on the transient outward (Ito) current of cardiomyocytes and underlying mechanism of action remain unclear. In the current study, 100 nM JZTX-V effectively inhibited the Ito current and extended the action potential duration (APD) of neonatal rat ventricular myocytes (NRVM). We further analyzed the effects of JZTX-V on Kv4.2, a cloned channel believed to underlie the Ito current in rat cardiomyocytes. JZTX-V inhibited the Kv4.2 current with a half-maximal inhibitory concentration (IC50) of 13 ± 1.7 nM. To establish the molecular mechanism underlying the inhibitory action of JZTX-V on Kv4.2, we performed alanine scanning mutagenesis of Kv4.2 and JZTX-V and assessed the effects of the mutations on binding activities of the proteins. Interestingly, the Kv4.2 mutations V285A, F289A, and V290A reduced the affinity for JZTX-V while I275A and L277A increased the affinity for JZTX-V. Moreover, mutation of positively charged residues (R20 and K22) of JZTX-V and the hydrophobic patch (formed by W5, M6, and W7) led to a significant reduction in toxin sensitivity, indicating that the hydrophobic patch and electrostatic interactions played key roles in the binding of JZTX-V with Kv4.2. Data from our study have shed light on the specific roles and molecular mechanisms of JZTX-V in the regulation of Ito potassium channels and supported its utility as a potential novel antiarrhythmic drug.
Collapse
Affiliation(s)
- Yiya Zhang
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha, China.,Key Laboratory of Organ Injury, Aging and Regenerative Medicine of Hunan Province, Central South University, Changsha, China.,The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Ji Luo
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Juan He
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Mingqiang Rong
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| | - Xiongzhi Zeng
- The National and Local Joint Engineering Laboratory of Animal Peptide Drug Development, College of Life Sciences, Hunan Normal University, Changsha, China
| |
Collapse
|
10
|
Calloe K. Doctoral Dissertation: The transient outward potassium current in healthy and diseased hearts. Acta Physiol (Oxf) 2019; 225 Suppl 717:e13225. [PMID: 30628199 DOI: 10.1111/apha.13225] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 11/20/2018] [Accepted: 11/21/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Kirstine Calloe
- Section for Anatomy; Biochemistry and Physiology; Department for Veterinary and Animal Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Frederiksberg C Denmark
| |
Collapse
|
11
|
Jiménez-Vargas JM, Possani LD, Luna-Ramírez K. Arthropod toxins acting on neuronal potassium channels. Neuropharmacology 2017; 127:139-160. [PMID: 28941737 DOI: 10.1016/j.neuropharm.2017.09.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 09/13/2017] [Accepted: 09/15/2017] [Indexed: 01/01/2023]
Abstract
Arthropod venoms are a rich mixture of biologically active compounds exerting different physiological actions across diverse phyla and affecting multiple organ systems including the central nervous system. Venom compounds can inhibit or activate ion channels, receptors and transporters with high specificity and affinity providing essential insights into ion channel function. In this review, we focus on arthropod toxins (scorpions, spiders, bees and centipedes) acting on neuronal potassium channels. A brief description of the K+ channels classification and structure is included and a compendium of neuronal K+ channels and the arthropod toxins that modify them have been listed. This article is part of the Special Issue entitled 'Venom-derived Peptides as Pharmacological Tools.'
Collapse
Affiliation(s)
- Juana María Jiménez-Vargas
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad, 2001, Colonia Chamilpa, Apartado Postal 510-3, Cuernavaca 62210, Mexico
| | - Lourival D Possani
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad, 2001, Colonia Chamilpa, Apartado Postal 510-3, Cuernavaca 62210, Mexico
| | - Karen Luna-Ramírez
- Illawarra Health and Medical Research Institute, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia.
| |
Collapse
|
12
|
Pucca MB, Cerni FA, Cordeiro FA, Peigneur S, Cunha TM, Tytgat J, Arantes EC. Ts8 scorpion toxin inhibits the Kv4.2 channel and produces nociception in vivo. Toxicon 2016; 119:244-52. [PMID: 27346450 DOI: 10.1016/j.toxicon.2016.06.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 06/13/2016] [Accepted: 06/22/2016] [Indexed: 11/18/2022]
Abstract
The venom from the scorpion Tityus serrulatus (Ts) has been extensively studied mainly because of its rich cocktail of neurotoxins. Neurotoxins are the major and the most known components based on their modulation of voltage-gated ion channels. Until now, electrophysiological studies demonstrated that the Ts venom comprises toxins that affect Nav and Kv channels. However, although many studies have been conducted in this field, many peptides from Ts venom await further studies, including Ts8 toxin. Here we report the isolation and electrophysiological study of Ts8. The toxin Ts19 Frag-II was used as negative control. Ts8 demonstrates, among 20 tested channels, to be a selective modulator of Kv4.2 channels. Based on studies investigating the involvement of Kv4.2 on controlling nociception, we further investigated the modulation of pain by Ts8. Using intraplantar injections, Ts8 induced overt nociception (licking and lifting behaviors) and decreased the mechanical nociceptive threshold (hyperalgesia). Furthermore, the hyperalgesia was prolonged when intrathecal injections were performed. Independent of the severity, most of the victims stung by Ts scorpions report an intense and persistent pain as the major manifestation. The new role of Ts8 on nociception could explain, at least partially, this phenomenon. Additionally, our study also stresses the involvement of toxins specific to Nav channels and inflammatory mediators on the Ts painful sting. This work provides useful insights for a better understanding of the prolonged and intense pain associated with Ts envenoming for the development of specific therapies.
Collapse
Affiliation(s)
- Manuela Berto Pucca
- Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Felipe Augusto Cerni
- Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Francielle Almeida Cordeiro
- Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Steve Peigneur
- Toxicology and Pharmacology, University of Leuven, Leuven, Belgium
| | - Thiago Mattar Cunha
- Department of Pharmacology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven, Leuven, Belgium
| | - Eliane Candiani Arantes
- Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
| |
Collapse
|
13
|
Yu H, Zou B, Wang X, Li M. Effect of tyrphostin AG879 on Kv 4.2 and Kv 4.3 potassium channels. Br J Pharmacol 2015; 172:3370-82. [PMID: 25752739 DOI: 10.1111/bph.13127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 02/25/2015] [Accepted: 03/02/2015] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND AND PURPOSE A-type potassium channels (IA) are important proteins for modulating neuronal membrane excitability. The expression and activity of Kv 4.2 channels are critical for neurological functions and pharmacological inhibitors of Kv 4.2 channels may have therapeutic potential for Fragile X syndrome. While screening various compounds, we identified tyrphostin AG879, a tyrosine kinase inhibitor, as a Kv 4.2 inhibitor from. In the present study we characterized the effect of AG879 on cloned Kv 4.2/Kv channel-interacting protein 2 (KChIP2) channels. EXPERIMENTAL APPROACH To screen the library of pharmacologically active compounds, the thallium flux assay was performed on HEK-293 cells transiently-transfected with Kv 4.2 cDNA using the Maxcyte transfection system. The effects of AG879 were further examined on CHO-K1 cells expressing Kv 4.2/KChIP2 channels using a whole-cell patch-clamp technique. KEY RESULTS Tyrphostin AG879 selectively and dose-dependently inhibited Kv 4.2 and Kv 4.3 channels. In Kv 4.2/KChIP2 channels, AG879 induced prominent acceleration of the inactivation rate, use-dependent block and slowed the recovery from inactivation. AG879 induced a hyperpolarizing shift in the voltage-dependence of the steady-state inactivation of Kv 4.2 channels without apparent effect on the V1/2 of the voltage-dependent activation. The blocking effect of AG879 was enhanced as channel inactivation increased. Furthermore, AG879 significantly inhibited the A-type potassium currents in the cultured hippocampus neurons. CONCLUSION AND IMPLICATIONS AG879 was identified as a selective and potent inhibitor the Kv 4.2 channel. AG879 inhibited Kv 4.2 channels by preferentially interacting with the open state and further accelerating their inactivation.
Collapse
Affiliation(s)
- Haibo Yu
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.,The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center and Johns Hopkins Ion Channel Center, Johns Hopkins University, Baltimore, MD, USA
| | - Beiyan Zou
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center and Johns Hopkins Ion Channel Center, Johns Hopkins University, Baltimore, MD, USA
| | - Xiaoliang Wang
- State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Min Li
- The Solomon H. Snyder Department of Neuroscience, High Throughput Biology Center and Johns Hopkins Ion Channel Center, Johns Hopkins University, Baltimore, MD, USA
| |
Collapse
|
14
|
Klint JK, Senff S, Saez NJ, Seshadri R, Lau HY, Bende NS, Undheim EAB, Rash LD, Mobli M, King GF. Production of recombinant disulfide-rich venom peptides for structural and functional analysis via expression in the periplasm of E. coli. PLoS One 2013; 8:e63865. [PMID: 23667680 PMCID: PMC3646780 DOI: 10.1371/journal.pone.0063865] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 04/06/2013] [Indexed: 11/27/2022] Open
Abstract
Disulfide-rich peptides are the dominant component of most animal venoms. These peptides have received much attention as leads for the development of novel therapeutic agents and bioinsecticides because they target a wide range of neuronal receptors and ion channels with a high degree of potency and selectivity. In addition, their rigid disulfide framework makes them particularly well suited for addressing the crucial issue of in vivo stability. Structural and functional characterization of these peptides necessitates the development of a robust, reliable expression system that maintains their native disulfide framework. The bacterium Escherichia coli has long been used for economical production of recombinant proteins. However, the expression of functional disulfide-rich proteins in the reducing environment of the E. coli cytoplasm presents a significant challenge. Thus, we present here an optimised protocol for the expression of disulfide-rich venom peptides in the periplasm of E. coli, which is where the endogenous machinery for production of disulfide-bonds is located. The parameters that have been investigated include choice of media, induction conditions, lysis methods, methods of fusion protein and peptide purification, and sample preparation for NMR studies. After each section a recommendation is made for conditions to use. We demonstrate the use of this method for the production of venom peptides ranging in size from 2 to 8 kDa and containing 2-6 disulfide bonds.
Collapse
Affiliation(s)
- Julie K. Klint
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Sebastian Senff
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Natalie J. Saez
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Radha Seshadri
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Ho Yee Lau
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Niraj S. Bende
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Eivind A. B. Undheim
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Lachlan D. Rash
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Mehdi Mobli
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| | - Glenn F. King
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia
| |
Collapse
|
15
|
Witzel K, Fischer P, Bähring R. Hippocampal A-type current and Kv4.2 channel modulation by the sulfonylurea compound NS5806. Neuropharmacology 2012; 63:1389-403. [PMID: 22964468 DOI: 10.1016/j.neuropharm.2012.08.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 08/16/2012] [Accepted: 08/18/2012] [Indexed: 12/24/2022]
Abstract
We examined the effects of the sulfonylurea compound NS5806 on neuronal A-type channel function. Using whole-cell patch-clamp we studied the effects of NS5806 on the somatodendritic A-type current (I(SA)) in cultured hippocampal neurons and the currents mediated by Kv4.2 channels coexpressed with different auxiliary β-subunits, including both Kv channel interacting proteins (KChIPs) and dipeptidyl aminopeptidase-related proteins (DPPs), in HEK 293 cells. The amplitude of the I(SA) component in hippocampal neurons was reduced in the presence of 20 μM NS5806. I(SA) decay kinetics were slowed and the recovery kinetics accelerated, but the voltage dependence of steady-state inactivation was shifted to more negative potentials by NS5806. The peak amplitudes of currents mediated by ternary Kv4.2 channel complexes, associated with DPP6-S (short splice-variant) and either KChIP2, KChIP3 or KChIP4, were potentiated and their macroscopic inactivation slowed by NS5806, whereas the currents mediated by binary Kv4.2 channels, associated only with DPP6-S, were suppressed, and the NS5806-mediated slowing of macroscopic inactivation was less pronounced. Neither potentiation nor suppression and no effect on current decay kinetics in the presence of NS5806 were observed for Kv4.2 channels associated with KChIP3 and the N-type inactivation-conferring DPP6a splice-variant. For all recombinant channel complexes, NS5806 slowed the recovery from inactivation and shifted the voltage dependence of steady-state inactivation to more negative potentials. Our results demonstrate the activity of NS5806 on native I(SA) and possible molecular correlates in the form of recombinant Kv4.2 channels complexed with different KChIPs and DPPs, and they shed some light on the mechanism of NS5806 action.
Collapse
Affiliation(s)
- Katrin Witzel
- Institut für Zelluläre und Integrative Physiologie, Zentrum für Experimentelle Medizin, Universitätsklinikum Hamburg-Eppendorf, Martinistr. 52, 20246 Hamburg, Germany
| | | | | |
Collapse
|
16
|
Towards therapeutic applications of arthropod venom k(+)-channel blockers in CNS neurologic diseases involving memory acquisition and storage. J Toxicol 2012; 2012:756358. [PMID: 22701481 PMCID: PMC3373146 DOI: 10.1155/2012/756358] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Accepted: 02/08/2012] [Indexed: 12/31/2022] Open
Abstract
Potassium channels are the most heterogeneous and widely distributed group of ion channels and play important functions in all cells, in both normal and pathological mechanisms, including learning and memory processes. Being fundamental for many diverse physiological processes, K+-channels are recognized as potential therapeutic targets in the treatment of several Central Nervous System (CNS) diseases, such as multiple sclerosis, Parkinson's and Alzheimer's diseases, schizophrenia, HIV-1-associated dementia, and epilepsy. Blockers of these channels are therefore potential candidates for the symptomatic treatment of these neuropathies, through their neurological effects. Venomous animals have evolved a wide set of toxins for prey capture and defense. These compounds, mainly peptides, act on various pharmacological targets, making them an innumerable source of ligands for answering experimental paradigms, as well as for therapeutic application. This paper provides an overview of CNS K+-channels involved in memory acquisition and storage and aims at evaluating the use of highly selective K+-channel blockers derived from arthropod venoms as potential therapeutic agents for CNS diseases involving learning and memory mechanisms.
Collapse
|
17
|
Bähring R, Barghaan J, Westermeier R, Wollberg J. Voltage sensor inactivation in potassium channels. Front Pharmacol 2012; 3:100. [PMID: 22654758 PMCID: PMC3358694 DOI: 10.3389/fphar.2012.00100] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 05/04/2012] [Indexed: 12/15/2022] Open
Abstract
In voltage-gated potassium (Kv) channels membrane depolarization causes movement of a voltage sensor domain. This conformational change of the protein is transmitted to the pore domain and eventually leads to pore opening. However, the voltage sensor domain may interact with two distinct gates in the pore domain: the activation gate (A-gate), involving the cytoplasmic S6 bundle crossing, and the pore gate (P-gate), located externally in the selectivity filter. How the voltage sensor moves and how tightly it interacts with these two gates on its way to adopt a relaxed conformation when the membrane is depolarized may critically determine the mode of Kv channel inactivation. In certain Kv channels, voltage sensor movement leads to a tight interaction with the P-gate, which may cause conformational changes that render the selectivity filter non-conductive (“P/C-type inactivation”). Other Kv channels may preferably undergo inactivation from pre-open closed-states during voltage sensor movement, because the voltage sensor temporarily uncouples from the A-gate. For this behavior, known as “preferential” closed-state inactivation, we introduce the term “A/C-type inactivation”. Mechanistically, P/C- and A/C-type inactivation represent two forms of “voltage sensor inactivation.”
Collapse
Affiliation(s)
- Robert Bähring
- Institut für Zelluläre und Integrative Physiologie, Zentrum für Experimentelle Medizin, Universitätsklinikum Hamburg-Eppendorf Hamburg, Germany
| | | | | | | |
Collapse
|
18
|
Characterization of voltage-dependent calcium channel blocking peptides from the venom of the tarantula Grammostola rosea. Toxicon 2011; 58:265-76. [PMID: 21740921 DOI: 10.1016/j.toxicon.2011.06.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 06/13/2011] [Accepted: 06/15/2011] [Indexed: 12/22/2022]
Abstract
Voltage-dependent calcium channel blocking peptides were purified and sequenced from the venom of the tarantula, Grammostola rosea. cDNAs encoding the peptide sequences were cloned from the venom gland cDNA library. The electrophysiological effects of the peptides on several types of voltage-dependent calcium channels were evaluated using a Xenopus laevis oocyte expression system. A peptide contained in one of the HPLC peak fractions inhibited P/Q type voltage-dependent calcium channels (Ca(v)2.1). The amino acid sequence of this peptide is identical to that of ω-grammotoxin SIA. A peptide from another discrete peak, which is identical to GsAFII except for one tryptophan residue in the C-terminus, inhibited L-type voltage-dependent calcium channels (Ca(v)1.2). A novel peptide, named GTx1-15 (Accession number, AB201016), shows 76.5% sequence homology with the sodium channel blocker phrixotoxin 3, however, GTx1-15 preferentially inhibited T-type voltage-dependent calcium channels (Ca(v)3.1). In silico secondary and tertiary structure prediction revealed that GTx1-15 and sodium channel blockers such as hainantoxin-IV, phrixotoxin 3, and ceratotoxin 2 show very similar β-strand composition, distribution of Optimal Docking Areas (continuous surface patches likely to be involved in protein-protein interactions), and surface electrostatic potential. These findings suggest that these peptide toxins evolved from common ancestors by gene duplication to maintain surface atmospheres appropriate for interaction with low-voltage-dependent ion channels.
Collapse
|
19
|
Lundby A, Jespersen T, Schmitt N, Grunnet M, Olesen SP, Cordeiro JM, Calloe K. Effect of the I(to) activator NS5806 on cloned K(V)4 channels depends on the accessory protein KChIP2. Br J Pharmacol 2010; 160:2028-44. [PMID: 20649599 PMCID: PMC2958647 DOI: 10.1111/j.1476-5381.2010.00859.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 02/09/2010] [Accepted: 03/22/2010] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND AND PURPOSE The compound NS5806 increases the transient outward current (I(to)) in canine ventricular cardiomyocytes and slows current decay. In human and canine ventricle, I(to) is thought to be mediated by K(V)4.3 and various ancillary proteins, yet, the exact subunit composition of I(to) channels is still debated. Here we characterize the effect of NS5806 on heterologously expressed putative I(to) channel subunits and other potassium channels. EXPERIMENTAL APPROACH Cloned K(V)4 channels were co-expressed with KChIP2, DPP6, DPP10, KCNE2, KCNE3 and K(V)1.4 in Xenopus laevis oocytes or CHO-K1 cells. KEY RESULTS NS5806 increased K(V)4.3/KChIP2 peak current amplitudes with an EC(50) of 5.3 +/- 1.5microM and significantly slowed current decay. KCNE2, KCNE3, DPP6 and DPP10 modulated K(V)4.3 currents and the response to NS5806, but current decay was slowed only in complexes containing KChIP2. The effect of NS5806 on K(V)4.2 was similar to that on K(V)4.3, and current decay was only slowed in presence of KChIP2. However, for K(V)4.1, the slowing of current decay by NS5806 was independent of KChIP2. K(V)1.4 was strongly inhibited by 10 microM NS5806 and K(V)1.5 was inhibited to a smaller extent. Effects of NS5806 on kinetics of currents generated by K(V)4.3/KChIP2/DPP6 with K(V)1.4 in oocytes could reproduce those on cardiac I(to) in canine ventricular myocytes. K(V)7.1, K(V)11.1 and K(ir)2 currents were unaffected by NS5806. CONCLUSION AND IMPLICATIONS NS5806 modulated K(V)4 channel gating depending on the presence of KChIP2, suggesting that NS5806 can potentially be used to address the molecular composition as well as the physiological role of cardiac I(to).
Collapse
Affiliation(s)
- A Lundby
- The Danish National Research Foundation Centre for Cardiac Arrhythmia, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | | | | | | | | | | |
Collapse
|
20
|
Su T, Cong W, Long Y, Luo A, Sun W, Deng W, Liao W. Altered expression of voltage-gated potassium channel 4.2 and voltage-gated potassium channel 4-interacting protein, and changes in intracellular calcium levels following lithium-pilocarpine-induced status epilepticus. Neuroscience 2008; 157:566-76. [DOI: 10.1016/j.neuroscience.2008.09.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Revised: 09/16/2008] [Accepted: 09/19/2008] [Indexed: 11/16/2022]
|
21
|
Diochot S. Precious Natural Peptides from Spider Venoms: New Tools for Studying Potassium Channels. TOXIN REV 2008. [DOI: 10.1080/07313830500237059] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
22
|
Role of N-terminal domain and accessory subunits in controlling deactivation-inactivation coupling of Kv4.2 channels. Biophys J 2007; 94:1276-94. [PMID: 17981906 DOI: 10.1529/biophysj.107.111344] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We examined the relationship between deactivation and inactivation in Kv4.2 channels. In particular, we were interested in the role of a Kv4.2 N-terminal domain and accessory subunits in controlling macroscopic gating kinetics and asked if the effects of N-terminal deletion and accessory subunit coexpression conform to a kinetic coupling of deactivation and inactivation. We expressed Kv4.2 wild-type channels and N-terminal deletion mutants in the absence and presence of Kv channel interacting proteins (KChIPs) and dipeptidyl aminopeptidase-like proteins (DPPs) in human embryonic kidney 293 cells. Kv4.2-mediated A-type currents at positive and deactivation tail currents at negative membrane potentials were recorded under whole-cell voltage-clamp and analyzed by multi-exponential fitting. The observed changes in Kv4.2 macroscopic inactivation kinetics caused by N-terminal deletion, accessory subunit coexpression, or a combination of the two maneuvers were compared with respective changes in deactivation kinetics. Extensive correlation analyses indicated that modulatory effects on deactivation closely parallel respective effects on inactivation, including both onset and recovery kinetics. Searching for the structural determinants, which control deactivation and inactivation, we found that in a Kv4.2 Delta 2-10 N-terminal deletion mutant both the initial rapid phase of macroscopic inactivation and tail current deactivation were slowed. On the other hand, the intermediate and slow phase of A-type current decay, recovery from inactivation, and tail current decay kinetics were accelerated in Kv4.2 Delta 2-10 by KChIP2 and DPPX. Thus, a Kv4.2 N-terminal domain, which may control both inactivation and deactivation, is not necessary for active modulation of current kinetics by accessory subunits. Our results further suggest distinct mechanisms for Kv4.2 gating modulation by KChIPs and DPPs.
Collapse
|
23
|
Estrada G, Villegas E, Corzo G. Spider venoms: a rich source of acylpolyamines and peptides as new leads for CNS drugs. Nat Prod Rep 2007; 24:145-61. [PMID: 17268611 DOI: 10.1039/b603083c] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Advances in NMR and mass spectrometry as well as in peptide biochemistry coupled to modern methods in electrophysiology have permitted the isolation and identification of numerous products from spider venoms, previously explored due to technical limitations. The chemical composition of spider venoms is diverse, ranging from low molecular weight organic compounds such as acylpolyamines to complex peptides. First, acylpolyamines (< 1000 Da) have an aromatic moiety linked to a hydrophilic lateral chain. They were characterized for the first time in spider venoms and are ligand-gated ion channel antagonists, which block mainly postsynaptic glutamate receptors in invertebrate and vertebrate nervous systems. Acylpolyamines represent the vast majority of organic components from the spider venom. Acylpolyamine analogues have proven to suppress hippocampal epileptic discharges. Moreover, acylpolyamines could suppress excitatory postsynaptic currents inducing Ca+ accumulation in neurons leading to protection against a brain ischemic insult. Second, short spider peptides (< 6000 Da) modulate ionic currents in Ca2+, Na+, or K+ voltage-gated ion channels. Such peptides may contain from three to four disulfide bridges. Some spider peptides act specifically to discriminate among Ca2+, Na+, or K+ ion channel subtypes. Their selective affinities for ion channel subfamilies are functional for mapping excitable cells. Furthermore, several of these peptides have proven to hyperpolarize peripheral neurons, which are associated with supplying sensation to the skin and skeletal muscles. Some spider N-type calcium ion channel blockers may be important for the treatment of chronic pain. A special group of spider peptides are the amphipathic and positively charged peptides. Their secondary structure is alpha-helical and they insert into the lipid cell membrane of eukaryotic or prokaryotic cells leading to the formation of pores and subsequently depolarizing the cell membrane. Acylpolyamines and peptides from spider venoms represent an interesting source of molecules for the design of novel pharmaceutical drugs.
Collapse
Affiliation(s)
- Georgina Estrada
- Instituto de Biotecnología, UNAM, Avenida Universidad 2001, Cuernavaca, Morelos 62210, México
| | | | | |
Collapse
|
24
|
Abstract
Voltage-activated ion channels open and close in response to changes in membrane voltage, a process that is crucial for electrical signaling in the nervous system. The venom from many poisonous creatures contains a diverse array of small protein toxins that bind to voltage-activated channels and modify the gating mechanism. Hanatoxin and a growing number of related tarantula toxins have been shown to inhibit activation of voltage-activated potassium (K(v)) channels by interacting with their voltage-sensing domains. This review summarizes our current understanding of the mechanism by which these toxins alter gating, the location of the toxin receptor within K(v) channels and the disposition of this receptor with respect to the lipid membrane. The conservation of tarantula toxin receptors among voltage-activated ion channels will also be discussed.
Collapse
Affiliation(s)
- Kenton J Swartz
- Molecular Physiology and Biophysics Section, Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
25
|
Judge SIV, Bever CT. Potassium channel blockers in multiple sclerosis: Neuronal Kv channels and effects of symptomatic treatment. Pharmacol Ther 2006; 111:224-59. [PMID: 16472864 DOI: 10.1016/j.pharmthera.2005.10.006] [Citation(s) in RCA: 200] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2005] [Accepted: 10/12/2005] [Indexed: 02/07/2023]
Abstract
Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by demyelination, with a relative sparing of axons. In MS patients, many neurologic signs and symptoms have been attributed to the underlying conduction deficits. The idea that neurologic function might be improved if conduction could be restored in CNS demyelinated axons led to the testing of potassium (K(+)) channel blockers as a symptomatic treatment. To date, only 2 broad-spectrum K(+) channel blockers, 4-aminopyridine (4-AP) and 3,4-diaminopyridine (3,4-DAP), have been tested in MS patients. Although both 4-AP and 3,4-DAP produce clear neurologic benefits, their use has been limited by toxicity. Here we review the current status of basic science and clinical research related to the therapeutic targeting of voltage-gated K(+) channels (K(v)) in MS. By bringing together 3 distinct but interrelated disciplines, we aim to provide perspective on a vast body of work highlighting the lengthy and ongoing process entailed in translating fundamental K(v) channel knowledge into new clinical treatments for patients with MS and other demyelinating diseases. Covered are (1) K(v) channel nomenclature, structure, function, and pharmacology; (2) classic and current experimental morphology and neurophysiology studies of demyelination and conduction deficits; and (3) a comprehensive overview of clinical trials utilizing 4-AP and 3,4-DAP in MS patients.
Collapse
Affiliation(s)
- Susan I V Judge
- MS Center of Excellence-East, Research and Neurology Services, VA Maryland Health Care System, USA.
| | | |
Collapse
|
26
|
Choi SJ, Parent R, Guillaume C, Deregnaucourt C, Delarbre C, Ojcius DM, Montagne JJ, Célérier ML, Phelipot A, Amiche M, Molgo J, Camadro JM, Guette C. Isolation and characterization of Psalmopeotoxin I and II: two novel antimalarial peptides from the venom of the tarantula Psalmopoeus cambridgei. FEBS Lett 2004; 572:109-17. [PMID: 15304333 DOI: 10.1016/j.febslet.2004.07.019] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Revised: 06/24/2004] [Accepted: 07/09/2004] [Indexed: 11/17/2022]
Abstract
Two novel peptides that inhibit the intra-erythrocyte stage of Plasmodium falciparum in vitro were identified in the venom of the Trinidad chevron tarantula, Psalmopoeus cambridgei. Psalmopeotoxin I (PcFK1) is a 33-residue peptide and Psalmopeotoxin II (PcFK2) has 28-amino acid residues; both have three disulfide bridges and belong to the Inhibitor Cystine Knot superfamily. The cDNAs encoding both peptides were cloned, and nucleotide sequence analysis showed that the peptides are synthesized with typical signal peptides and pro-sequences that are cleaved at a basic doublet before secretion of the mature peptides. The IC(5O) of PcFK1 for inhibiting P. falciparum growth was 1.59+/-1.15 microM and that of PcFK2 was 1.15+/-0.95 microM. PcFK1 was adsorbed strongly to uninfected erythrocytes, but PcFK2 was not. Neither peptide has significant hemolytic activity at 10 microM. Electrophysiological recordings in isolated frog and mouse neuromuscular preparations revealed that the peptides (at up to 9.3 microM) do not affect neuromuscular transmission or quantal transmitter release. PcFK1 and PcFK2 do not affect the growth or viability of human epithelial cells, nor do they have any antifungal or antibacterial activity at 20 microM. Thus, PcFK1 and PcFK2 seem to interact specifically with infected erythrocytes. They could therefore be promising tools for antimalaria research and be the basis for the rational development of antimalarial drugs.
Collapse
Affiliation(s)
- Soo-Jin Choi
- Laboratoire d'Ingénierie des Protéines et Contrôle Métabolique, Dept. de Biologie des Génomes, Institut Jacques Monod, UMR 7592, CNRS -- Universités Paris 6 and 7, 2 place Jussieu, 75251 Paris Cedex 05, France
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|