UniProtKB - Q8I0L5 (KA152_MESMA)
Potassium channel toxin alpha-KTx 15.2
Functioni
Blocks both human ERG1/Kv11.1/KCNH2 potassium channels (in a reversible manner) (PubMed:14599291) and A-type voltage-gated potassium channels Kv4/KCND (in an irreversible manner) (PubMed:11457451, PubMed:12473099, PubMed:12637022).
The presence of the Kv4-associated proteins DPP6 or DPP10 is mandatory to have high-affinity blockade of Kv4.2/KCND2 and Kv4.3/KCND3 channels (By similarity).
In contrast, the presence of the Kv4-associated protein KChIP1/KCNIP1 does not enhance the affinity blockade (By similarity).
May dispose of two functional faces (A and B); the two basic residues (Arg-40 and Lys-41) on the alpha-helix side of the peptide that blocks the hERG current (face A) and the typical dyad through which it blocks A-type currents on the beta-sheet side (face B) (PubMed:14599291).
In adult rat brain, it binds to sites in the striatum, hippocampus, superior colliculus, and cerebellum. It shares the same target in rat brain than AaTX1 (AC Q867F4) and AmmTX3 (AC P60208). In DPP6 knockout mice, A-type currents are much less affected by the toxin than in wild-type mice (PubMed:23440961).
By similarity4 PublicationsMiscellaneous
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sitei | 28 | Hot spot residue in hERG blocking currents1 Publication | 1 | |
Sitei | 40 | Hot spot basic residue in hERG blocking currents1 Publication | 1 | |
Sitei | 41 | Hot spot basic residue in hERG blocking currents1 Publication | 1 | |
Sitei | 49 | Basic residue of the functional dyadBy similarity | 1 | |
Sitei | 58 | Aromatic residue of the functional dyadBy similarity | 1 |
GO - Molecular functioni
- ion channel inhibitor activity Source: InterPro
- potassium channel regulator activity Source: UniProtKB-KW
- toxin activity Source: UniProtKB-KW
Keywordsi
Molecular function | Ion channel impairing toxin, Neurotoxin, Potassium channel impairing toxin, Toxin, Voltage-gated potassium channel impairing toxin |
Protein family/group databases
TCDBi | 8.B.8.1.2, the Alpha-ktx15 scorpion toxin (Alpha-ktx15) family |
Names & Taxonomyi
Protein namesi | Recommended name: Potassium channel toxin alpha-KTx 15.2CuratedAlternative name(s): BmTX31 Publication BmTX3A1 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
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 58 – 59 | Missing : Decrease in blocking of A-type voltage-gated potassium channels, loss of inhibition of Kv4.1/KCND1 and Kv4.3/KCND3. 2 Publications | 2 |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Signal peptidei | 1 – 22 | 2 PublicationsAdd BLAST | 22 | |
ChainiPRO_0000035319 | 23 – 59 | Potassium channel toxin alpha-KTx 15.22 PublicationsAdd BLAST | 37 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Modified residuei | 23 | Pyrrolidone carboxylic acid2 Publications | 1 | |
Disulfide bondi | 30 ↔ 50 | 1 Publication | ||
Disulfide bondi | 35 ↔ 55 | 1 Publication | ||
Disulfide bondi | 39 ↔ 57 | 1 Publication |
Keywords - PTMi
Disulfide bond, Pyrrolidone carboxylic acidExpressioni
Tissue specificityi
Family & Domainsi
Domaini
Sequence similaritiesi
Keywords - Domaini
SignalFamily and domain databases
Gene3Di | 3.30.30.10, 1 hit |
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
10 20 30 40 50
MKFSSIILLT LLICSMSKFG NCQVETNVKC QGGSCASVCR KAIGVAAGKC
INGRCVCYP
Mass spectrometryi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | AF541980 mRNA Translation: AAN34656.1 AY156725 Genomic DNA Translation: AAN85572.1 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | AF541980 mRNA Translation: AAN34656.1 AY156725 Genomic DNA Translation: AAN85572.1 |
3D structure databases
AlphaFoldDBi | Q8I0L5 |
SMRi | Q8I0L5 |
ModBasei | Search... |
Protein family/group databases
TCDBi | 8.B.8.1.2, the Alpha-ktx15 scorpion toxin (Alpha-ktx15) family |
Family and domain databases
Gene3Di | 3.30.30.10, 1 hit |
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 |
MobiDBi | Search... |
Entry informationi
Entry namei | KA152_MESMA | |
Accessioni | Q8I0L5Primary (citable) accession number: Q8I0L5 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | September 26, 2003 |
Last sequence update: | March 1, 2003 | |
Last modified: | May 25, 2022 | |
This is version 77 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