UniProtKB - P86408 (SCXN1_MESEU)
Sodium channel neurotoxin MeuNaTxalpha-1
Functioni
Alpha toxins bind voltage-independently at site-3 of sodium channels (Nav) and inhibit the inactivation of the activated channels, thereby blocking neuronal transmission. This toxin inhibits inactivation of Nav1.6/SCN8A (EC(50)=3.1 µM) and drosophila DmNav1 (EC(50)=1.17 µM) (PubMed:21969612, Ref. 2, PubMed:33051988).
It also shows a weak inhibition of inactivation on Nav1.2/SCN2A Nav1.3/SCN3A, and Nav1.7/SCN9A (PubMed:21969612, PubMed:33051988).
The toxin (1 µM) does not significantly shift the midpoint of activation at the two channels, but induces a significant depolarizing shift in the V(1/2) of inactivation of the channels (PubMed:21969612).
The toxin has also been shown to dose-dependently stimulates intracellular signaling in DRG neurons through activation of two kinases (type II protein kinase A (PKA-II) and MAP kinases 1/3 (MAPK1/MAPK3)) (PubMed:33051988).
Nav1.2/SCN2A is strongly suggested to be the target channel predominantly involved in this activation (PubMed:33051988).
In vivo, the toxin induces a dose-dependent thermal hyperalgesia lasting 30-45 minutes (PubMed:33051988).
2 PublicationsMiscellaneous
GO - Molecular functioni
- sodium channel inhibitor activity Source: UniProtKB
- toxin activity Source: UniProtKB-KW
GO - Biological processi
- defense response Source: InterPro
- modulation by symbiont of host nervous system process Source: InterPro
Keywordsi
Molecular function | Ion channel impairing toxin, Neurotoxin, Toxin, Voltage-gated sodium channel impairing toxin |
Names & Taxonomyi
Protein namesi | Recommended name: Sodium channel neurotoxin MeuNaTxalpha-12 Publications |
Organismi | Mesobuthus eupeus (Lesser Asian scorpion) (Buthus eupeus) |
Taxonomic identifieri | 34648 [NCBI] |
Taxonomic lineagei | Eukaryota › Metazoa › Ecdysozoa › Arthropoda › Chelicerata › Arachnida › Scorpiones › Buthida › Buthoidea › Buthidae › Mesobuthus |
Subcellular locationi
Extracellular region or secreted
- Secreted 1 Publication
Extracellular region or secreted
- extracellular region Source: UniProtKB
Keywords - Cellular componenti
SecretedPathology & Biotechi
Toxic dosei
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Signal peptidei | 1 – 19 | 3 PublicationsAdd BLAST | 19 | |
ChainiPRO_0000401119 | 20 – 83 | Sodium channel neurotoxin MeuNaTxalpha-11 PublicationAdd BLAST | 64 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Disulfide bondi | 31 ↔ 82 | Combined sources1 Publication | ||
Disulfide bondi | 35 ↔ 55 | 1 Publication | ||
Disulfide bondi | 41 ↔ 65 | 1 Publication | ||
Disulfide bondi | 45 ↔ 67 | Combined sources1 Publication | ||
Modified residuei | 83 | Asparagine amide2 Publications | 1 |
Post-translational modificationi
Keywords - PTMi
Amidation, Disulfide bondExpressioni
Tissue specificityi
Structurei
Secondary structure
3D structure databases
AlphaFoldDBi | P86408 |
SMRi | P86408 |
ModBasei | Search... |
PDBe-KBi | Search... |
Family & Domainsi
Domains and Repeats
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Domaini | 21 – 83 | LCN-type CS-alpha/betaPROSITE-ProRule annotationAdd BLAST | 63 |
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 27 – 31 | Specificity module, loop 11 Publication | 5 | |
Regioni | 58 – 62 | Specificity module, loop 21 Publication | 5 | |
Regioni | 75 – 83 | Specificity module, loop 31 Publication | 9 |
Domaini
Sequence similaritiesi
Keywords - Domaini
SignalFamily and domain databases
CDDi | cd00107, Knot1, 1 hit |
Gene3Di | 3.30.30.10, 1 hit |
InterProi | View protein in InterPro IPR044062, LCN-type_CS_alpha_beta_dom IPR003614, Scorpion_toxin-like IPR036574, Scorpion_toxin-like_sf IPR018218, Scorpion_toxinL IPR002061, Scorpion_toxinL/defensin |
Pfami | View protein in Pfam PF00537, Toxin_3, 1 hit |
PRINTSi | PR00285, SCORPNTOXIN |
SMARTi | View protein in SMART SM00505, Knot1, 1 hit |
SUPFAMi | SSF57095, SSF57095, 1 hit |
PROSITEi | View protein in PROSITE PS51863, LCN_CSAB, 1 hit |
i Sequence
Sequence statusi: Complete.
: The displayed sequence is further processed into a mature form. Sequence processingi
10 20 30 40 50
MNSLVMISLA LLVMTGVESV RDGYIADDKN CAYFCGRNAY CDEECKKKGA
60 70 80
ESGYCQWAGQ YGNACWCYKL PDKVPIKVSG KCNGR
Mass spectrometryi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | EF445066 Genomic DNA Translation: ABR21041.1 HM989910 mRNA Translation: ADT82850.1 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | EF445066 Genomic DNA Translation: ABR21041.1 HM989910 mRNA Translation: ADT82850.1 |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
6THI | NMR | - | A | 20-83 | [»] | |
AlphaFoldDBi | P86408 | |||||
SMRi | P86408 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Family and domain databases
CDDi | cd00107, Knot1, 1 hit |
Gene3Di | 3.30.30.10, 1 hit |
InterProi | View protein in InterPro IPR044062, LCN-type_CS_alpha_beta_dom IPR003614, Scorpion_toxin-like IPR036574, Scorpion_toxin-like_sf IPR018218, Scorpion_toxinL IPR002061, Scorpion_toxinL/defensin |
Pfami | View protein in Pfam PF00537, Toxin_3, 1 hit |
PRINTSi | PR00285, SCORPNTOXIN |
SMARTi | View protein in SMART SM00505, Knot1, 1 hit |
SUPFAMi | SSF57095, SSF57095, 1 hit |
PROSITEi | View protein in PROSITE PS51863, LCN_CSAB, 1 hit |
MobiDBi | Search... |
Entry informationi
Entry namei | SCXN1_MESEU | |
Accessioni | P86408Primary (citable) accession number: P86408 Secondary accession number(s): E4VP24, E7CZY7 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | November 30, 2010 |
Last sequence update: | July 3, 2019 | |
Last modified: | May 25, 2022 | |
This is version 30 of the entry and version 2 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Animal Toxin Annotation Program |
Miscellaneousi
Keywords - Technical termi
3D-structure, Direct protein sequencingDocuments
- PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families