UniProtKB - Q9TVX3 (KAX53_MESMA)
Protein
Potassium channel toxin alpha-KTx 5.3
Gene
N/A
Organism
Mesobuthus martensii (Manchurian scorpion) (Buthus martensii)
Status
Functioni
Blocks small conductance calcium-activated potassium channels (KCNN, SK) (PubMed:9151979). Has also been shown to weakly inhibit Kv11.1/KCNH2/ERG1, Kv1.2/KCNA2, Kv1.3/KCNA3 and Kv2.1/KCNB1 voltage-gated potassium channels (PubMed:29483648).2 Publications
Miscellaneous
Toxicity experiments on mutants are done without C-terminal amidation.1 Publication
GO - Molecular functioni
- ion channel inhibitor activity Source: InterPro
- toxin activity Source: UniProtKB-KW
Keywordsi
Molecular function | Calcium-activated potassium channel impairing toxin, Ion channel impairing toxin, Neurotoxin, Potassium channel impairing toxin, Toxin |
Names & Taxonomyi
Protein namesi | Recommended name: Potassium channel toxin alpha-KTx 5.3Alternative name(s): Neurotoxin BmP051 Publication Potassium ion channel blocker P051 Publication |
Organismi | Mesobuthus martensii (Manchurian scorpion) (Buthus martensii) |
Taxonomic identifieri | 34649 [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-SubCell
Keywords - Cellular componenti
SecretedPathology & Biotechi
Toxic dosei
LD50 is 1.85 µg/kg by intracerebroventricular injection into mice.2 Publications
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 34 | K → A: 86.4% loss of toxicity. 100% loss of toxicity; when associated with A-41. 1 Publication | 1 | |
Mutagenesisi | 37 | Q → P: 97.5% loss of toxicity. 1 Publication | 1 | |
Mutagenesisi | 41 | R → A: 83.0% loss of toxicity. 100% loss of toxicity; when associated with A-34. 1 Publication | 1 | |
Mutagenesisi | 50 – 52 | IGD → MNG: 68.4% loss of toxicity. 1 Publication | 3 | |
Mutagenesisi | 59 | H → A: 55.4% loss of toxicity. 1 Publication | 1 |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Signal peptidei | 1 – 28 | 1 PublicationAdd BLAST | 28 | |
ChainiPRO_0000035324 | 29 – 59 | Potassium channel toxin alpha-KTx 5.31 PublicationAdd BLAST | 31 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Disulfide bondi | 31 ↔ 49 | By similarity | ||
Disulfide bondi | 36 ↔ 54 | By similarity | ||
Disulfide bondi | 40 ↔ 56 | By similarity | ||
Modified residuei | 59 | Histidine amide1 Publication | 1 |
Keywords - PTMi
Amidation, Disulfide bondExpressioni
Tissue specificityi
Expressed by the venom gland.1 Publication
Structurei
3D structure databases
ProteinModelPortali | Q9TVX3 |
SMRi | Q9TVX3 |
ModBasei | Search... |
MobiDBi | Search... |
Family & Domainsi
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 34 – 37 | [R/K]XCQ motifCurated | 4 |
Sequence similaritiesi
Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 05 subfamily.Curated
Keywords - Domaini
SignalFamily and domain databases
InterProi | View protein in InterPro IPR036574 Scorpion_toxin-like_sf IPR001947 Scorpion_toxinS_K_inh |
Pfami | View protein in Pfam PF00451 Toxin_2, 1 hit |
SUPFAMi | SSF57095 SSF57095, 1 hit |
PROSITEi | View protein in PROSITE PS01138 SCORP_SHORT_TOXIN, 1 hit |
i Sequence
Sequence statusi: Complete.
: The displayed sequence is further processed into a mature form. Sequence processingi
Q9TVX3-1 [UniParc]FASTAAdd to basket
10 20 30 40 50
MHNYYKIVLI MVAFFAVIIT FSNIQVEGAV CNLKRCQLSC RSLGLLGKCI
60
GDKCECVKHG K
Mass spectrometryi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | AF079064 mRNA Translation: AAD47378.1 AF095780 Genomic DNA Translation: AAF03044.1 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | AF079064 mRNA Translation: AAD47378.1 AF095780 Genomic DNA Translation: AAF03044.1 |
3D structure databases
ProteinModelPortali | Q9TVX3 |
SMRi | Q9TVX3 |
ModBasei | Search... |
MobiDBi | Search... |
Protocols and materials databases
Structural Biology Knowledgebase | Search... |
Family and domain databases
InterProi | View protein in InterPro IPR036574 Scorpion_toxin-like_sf IPR001947 Scorpion_toxinS_K_inh |
Pfami | View protein in Pfam PF00451 Toxin_2, 1 hit |
SUPFAMi | SSF57095 SSF57095, 1 hit |
PROSITEi | View protein in PROSITE PS01138 SCORP_SHORT_TOXIN, 1 hit |
ProtoNeti | Search... |
Entry informationi
Entry namei | KAX53_MESMA | |
Accessioni | Q9TVX3Primary (citable) accession number: Q9TVX3 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | December 19, 2001 |
Last sequence update: | May 1, 2000 | |
Last modified: | February 13, 2019 | |
This is version 70 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Animal Toxin Annotation Program |
Miscellaneousi
Keywords - Technical termi
Direct protein sequencingDocuments
- Scorpion potassium channel toxins
Nomenclature of scorpion potassium channel toxins and list of entries - SIMILARITY comments
Index of protein domains and families