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PLoS One
2015 Jun 05;106:e0128578. doi: 10.1371/journal.pone.0128578.
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The Scorpion Toxin Tf2 from Tityus fasciolatus Promotes Nav1.3 Opening.
Camargos TS
,
Bosmans F
,
Rego SC
,
Mourão CB
,
Schwartz EF
.
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We identified Tf2, the first β-scorpion toxin from the venom of the Brazilian scorpion Tityus fasciolatus. Tf2 is identical to Tb2-II found in Tityus bahiensis. We found that Tf2 selectively activates human (h)Nav1.3, a neuronal voltage-gated sodium (Nav) subtype implicated in epilepsy and nociception. Tf2 shifts hNav1.3 activation voltage to more negative values, thereby opening the channel at resting membrane potentials. Seven other tested mammalian Nav channels (Nav1.1-1.2; Nav1.4-1.8) expressed in Xenopus oocytes are insensitive upon application of 1 μM Tf2. Therefore, the identification of Tf2 represents a unique addition to the repertoire of animal toxins that can be used to investigate Nav channel function.
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Fig 2. Tf2 sequence and alignment with scorpion Nav channel toxins.(A) The nucleotide sequence of Tf2 was obtained by HiSeq (Illumina, USA). Signal peptide is underlined, mature peptide is highlighted in gray, and the amidation set point is marked in italic. (B) Multiple sequence alignment of Tf2 with other Nav channel toxins. Toxins are presented by their short names and UniProt KB codes. Capital letters denote amino acids. Lower-case letters denote: h, hydrophobic; s, small; b, big; p, polar; t, tiny; a, aromatic; l, aliphatic. Positive (+) and negative (-) amino acid residues that are part of the consensus sequence are also colored. Cys residues are shaded in black. aa means amino acid residues, and %Id is the percentage of sequence identity with Tf2.
Fig 3. Structural comparison between Tf2 and other Nav channel toxins.(A) Structural alignment between Tf2 (in blue) and five other Nav channel scorpion toxins—Ts1, Ts2, CssII, CssIV, and AaHII (in gray). (B) Comparison of electrostatic potentials between the toxins Tf2, Ts1, Ts2, CssII, CssIV, and AaHII. The figure shows charge distribution along the toxin surface, divided into faces A and B. Shown in red are acidic residues whereas blue represents basic residues; in white, neutral regions are shown.
Fig 4. Effect of Tf2 on Nav channel isoforms expressed in X. laevis oocytes.Shown on the left in each column is a representative trace of experimental Na+ currents obtained by depolarizing the membrane to a suitable voltage from a holding potential of -90mV, at -25mV for Nav 1.1–1.2, 1.4–1.7, at -40mV for Nav1.3, and at 20mV for Nav1.8. Shown on the right in each column is a deduced conductance (G)—voltage (V) relationship before (black) and after (red) the application of 1μM Tf2. This concentration only influences the activation of hNav1.3. Data is shown as mean ± SEM of n > 3.
Fig 5. Sequence alignment of the domain II paddle motif in 8 mammalian Nav channel isoforms.Figure shows a sequence alignment of the domain II paddle motif as found in 8 mammalian Nav channel isoforms. As a reference, the number in italic indicates the coordinates of the first Gly residue in hNav1.1. Although the Ile in hNav1.3 (position 830 according to hNav1.3 coordinates, 840 according to hNav1.1 coordinates) differs from the Phe found in other neuronal isoforms, this residue is not present within the paddle motif and may not be accessible to Tf2. The Ser at position 842 (hNav1.3 coordinates—indicated in red) is unique among hNav1.1–1.3.
Fig 1. Purification and molecular mass determination of Tf2.(A) Chromatography by RP-HPLC of 1 mg of T. fasciolatus crude venom. Fractionation was performed on a C18 analytical column, using a linear gradient from 0% solvent A (0.12% TFA in water) to 60% solvent B (0.10% TFA in acetonitrile) over 60 min at a flow rate of 1 mL/min, with detection at a wavelength of 216 and 280nm. The component eluted at 38.5% of acetonitrile corresponds to Tf2. (B-D) Three additional chromatographic protocols performed to obtain pure Tf2. (B) Linear gradient of B solvent, from 25 to 45% B in 40 minutes, at room temperature (22°C). (C) Linear gradient of B solvent, from 25 to 45% of B in 40 minutes, at 45°C. (D) Linear gradient of B solvent, from 30 to 40% of B in 40 minutes, at 45°C. Inset on (A) shows mass spectrometry analysis of Tf2 by micrOTOF-Q II, presenting the monoisotopic distribution of the +7 charged ion ([M+7H]7+ = 993.7050), which is equivalent to [M+H]+ 6949.9350 Da.
Alami,
Characterization of Amm VIII from Androctonus mauretanicus mauretanicus: a new scorpion toxin that discriminates between neuronal and skeletal sodium channels.
2003, Pubmed,
Xenbase
Alami,
Characterization of Amm VIII from Androctonus mauretanicus mauretanicus: a new scorpion toxin that discriminates between neuronal and skeletal sodium channels.
2003,
Pubmed
,
Xenbase
Altschul,
Basic local alignment search tool.
1990,
Pubmed
Bende,
A distinct sodium channel voltage-sensor locus determines insect selectivity of the spider toxin Dc1a.
2014,
Pubmed
Benzinger,
A specific interaction between the cardiac sodium channel and site-3 toxin anthopleurin B.
1998,
Pubmed
Bezanilla,
How membrane proteins sense voltage.
2008,
Pubmed
Bosmans,
Deconstructing voltage sensor function and pharmacology in sodium channels.
2008,
Pubmed
,
Xenbase
Campos,
Voltage-dependent displacement of the scorpion toxin Ts3 from sodium channels and its implication on the control of inactivation.
2004,
Pubmed
Campos,
beta-Scorpion toxin modifies gating transitions in all four voltage sensors of the sodium channel.
2007,
Pubmed
,
Xenbase
Campos,
Alpha-scorpion toxin impairs a conformational change that leads to fast inactivation of muscle sodium channels.
2008,
Pubmed
,
Xenbase
Capes,
Gating transitions in the selectivity filter region of a sodium channel are coupled to the domain IV voltage sensor.
2012,
Pubmed
Cestèle,
Voltage sensor-trapping: enhanced activation of sodium channels by beta-scorpion toxin bound to the S3-S4 loop in domain II.
1998,
Pubmed
Cestèle,
Structure and function of the voltage sensor of sodium channels probed by a beta-scorpion toxin.
2006,
Pubmed
Cha,
Voltage sensors in domains III and IV, but not I and II, are immobilized by Na+ channel fast inactivation.
1999,
Pubmed
,
Xenbase
Chanda,
Tracking voltage-dependent conformational changes in skeletal muscle sodium channel during activation.
2002,
Pubmed
,
Xenbase
Chippaux,
Epidemiology of scorpionism: a global appraisal.
2008,
Pubmed
Coelho,
Functional and structural study comparing the C-terminal amidated β-neurotoxin Ts1 with its isoform Ts1-G isolated from Tityus serrulatus venom.
2014,
Pubmed
Cohen,
Common features in the functional surface of scorpion beta-toxins and elements that confer specificity for insect and mammalian voltage-gated sodium channels.
2005,
Pubmed
Cologna,
Investigation of the relationship between the structure and function of Ts2, a neurotoxin from Tityus serrulatus venom.
2012,
Pubmed
,
Xenbase
Darbon,
Photoaffinity labeling of alpha- and beta- scorpion toxin receptors associated with rat brain sodium channel.
1983,
Pubmed
Estacion,
A sodium channel mutation linked to epilepsy increases ramp and persistent current of Nav1.3 and induces hyperexcitability in hippocampal neurons.
2010,
Pubmed
Estrada,
Four disulfide-bridged scorpion beta neurotoxin CssII: heterologous expression and proper folding in vitro.
2007,
Pubmed
Estrada,
Addition of positive charges at the C-terminal peptide region of CssII, a mammalian scorpion peptide toxin, improves its affinity for sodium channels Nav1.6.
2011,
Pubmed
Felix,
Functional assay of voltage-gated sodium channels using membrane potential-sensitive dyes.
2004,
Pubmed
Gilchrist,
Crystallographic insights into sodium-channel modulation by the β4 subunit.
2013,
Pubmed
,
Xenbase
Gilchrist,
Animal toxins influence voltage-gated sodium channel function.
2014,
Pubmed
Goodstadt,
CHROMA: consensus-based colouring of multiple alignments for publication.
2001,
Pubmed
Guerrero-Vargas,
Identification and phylogenetic analysis of Tityus pachyurus and Tityus obscurus novel putative Na+-channel scorpion toxins.
2012,
Pubmed
Gur,
Elucidation of the molecular basis of selective recognition uncovers the interaction site for the core domain of scorpion alpha-toxins on sodium channels.
2011,
Pubmed
,
Xenbase
Hains,
Sodium channel expression and the molecular pathophysiology of pain after SCI.
2007,
Pubmed
Horn,
Immobilizing the moving parts of voltage-gated ion channels.
2000,
Pubmed
Housset,
Crystal structure of toxin II from the scorpion Androctonus australis Hector refined at 1.3 A resolution.
1994,
Pubmed
Humphrey,
VMD: visual molecular dynamics.
1996,
Pubmed
Kalia,
From foe to friend: using animal toxins to investigate ion channel function.
2015,
Pubmed
Karbat,
Molecular basis of the high insecticidal potency of scorpion alpha-toxins.
2004,
Pubmed
Karbat,
Partial agonist and antagonist activities of a mutant scorpion beta-toxin on sodium channels.
2010,
Pubmed
Kelley,
Protein structure prediction on the Web: a case study using the Phyre server.
2009,
Pubmed
Kharrat,
Structure-activity relationships of scorpion alpha-neurotoxins: contribution of arginine residues.
1990,
Pubmed
Larkin,
Clustal W and Clustal X version 2.0.
2007,
Pubmed
Leipold,
Subtype specificity of scorpion beta-toxin Tz1 interaction with voltage-gated sodium channels is determined by the pore loop of domain 3.
2006,
Pubmed
Leipold,
Scorpion β-toxin interference with NaV channel voltage sensor gives rise to excitatory and depressant modes.
2012,
Pubmed
Marcotte,
Effects of Tityus serrulatus scorpion toxin gamma on voltage-gated Na+ channels.
1997,
Pubmed
,
Xenbase
Martin-Eauclaire,
A surface plasmon resonance approach to monitor toxin interactions with an isolated voltage-gated sodium channel paddle motif.
2015,
Pubmed
,
Xenbase
McNicholas,
Presenting your structures: the CCP4mg molecular-graphics software.
2011,
Pubmed
Mihailescu,
Structural interactions of a voltage sensor toxin with lipid membranes.
2014,
Pubmed
Pedraza Escalona,
Scorpion beta-toxins and voltage-gated sodium channels: interactions and effects.
2013,
Pubmed
Petersen,
SignalP 4.0: discriminating signal peptides from transmembrane regions.
2011,
Pubmed
Pimenta,
Purification, amino-acid sequence and partial characterization of two toxins with anti-insect activity from the venom of the South American scorpion Tityus bahiensis (Buthidae).
2001,
Pubmed
Pinheiro,
Structural analysis of Tityus serrulatus Ts1 neurotoxin at atomic resolution: insights into interactions with Na+ channels.
2003,
Pubmed
Pintar,
Solution structure of toxin 2 from centruroides noxius Hoffmann, a beta-scorpion neurotoxin acting on sodium channels.
1999,
Pubmed
Polikarpov,
Crystal structure of neurotoxin Ts1 from Tityus serrulatus provides insights into the specificity and toxicity of scorpion toxins.
1999,
Pubmed
Possani,
Scorpion toxins from Centruroides noxius and Tityus serrulatus. Primary structures and sequence comparison by metric analysis.
1985,
Pubmed
Rogers,
Molecular determinants of high affinity binding of alpha-scorpion toxin and sea anemone toxin in the S3-S4 extracellular loop in domain IV of the Na+ channel alpha subunit.
1996,
Pubmed
Sampaio,
Further characterization of toxins T1IV (TsTX-III) and T2IV from Tityus serrulatus scorpion venom.
1991,
Pubmed
Saucedo,
Solution structure of native and recombinant expressed toxin CssII from the venom of the scorpion Centruroides suffusus suffusus, and their effects on Nav1.5 sodium channels.
2012,
Pubmed
Sheets,
The Na channel voltage sensor associated with inactivation is localized to the external charged residues of domain IV, S4.
1999,
Pubmed
Sheets,
The role of the putative inactivation lid in sodium channel gating current immobilization.
2000,
Pubmed
Söding,
Protein homology detection by HMM-HMM comparison.
2005,
Pubmed
Vanoye,
Novel SCN3A variants associated with focal epilepsy in children.
2014,
Pubmed
Wagner,
Purification and primary structure determination of Tf4, the first bioactive peptide isolated from the venom of the Brazilian scorpion Tityus fasciolatus.
2003,
Pubmed
Wang,
Mapping the receptor site for alpha-scorpion toxins on a Na+ channel voltage sensor.
2011,
Pubmed
Zhang,
Mapping the interaction site for a β-scorpion toxin in the pore module of domain III of voltage-gated Na(+) channels.
2012,
Pubmed
el Ayeb,
Use of antibodies specific to defined regions of scorpion alpha-toxin to study its interaction with its receptor site on the sodium channel.
1986,
Pubmed