P0C908 (KAX3A_BUTOS) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Potassium channel toxin alpha-KTx 3.10 Alternative name(s): BoiTx1
Organism	Buthus occitanus israelis (Common yellow scorpion)
Taxonomic identifier	539894 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Ecdysozoa › Panarthropoda › Arthropoda › Chelicerata › Arachnida › Scorpiones › Buthida › Buthoidea › Buthidae › Buthus › Buthus occitanus

Protein attributes

Sequence length	59 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Inhibits insect potassium channel. Is at least a hundred-fold more potent against the Drosophila Shaker channel than towards its mammalian homologs Kv1.1/KCNA1 and Kv1.3/KCNA3. Ref.1
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland.
Miscellaneous	Mammalian potassium channels (Kv2.1/KCNB1, Kir1.1/KCNJ1, Kv3.4/KCNC4, Kv4.2/KCND2, Kv7.1/KCNQ1, Kv7.2/KCNQ2, Kv7.3/KCNQ3 and Kv11.1/KCNH2) are even less affected by this toxin (Ref.1).
Sequence similarities	Belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 3 subfamily.
Mass spectrometry	Molecular mass is 4015.6 Da from positions 23 - 59. Determined by MALDI. Ref.1

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ion channel impairing toxin Neurotoxin Potassium channel inhibitor Toxin
PTM	Disulfide bond
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological_process	pathogenesis Inferred from electronic annotation. Source: InterPro
Cellular_component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	potassium channel inhibitor activity Inferred from electronic annotation. Source: UniProtKB-KW
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Signal peptide	1 – 22	22	Ref.1
	Peptide	23 – 59	37	Potassium channel toxin alpha-KTx 3.10 Ref.1		PRO_0000368016
Amino acid modifications
	Disulfide bond	30 ↔ 50		By similarity
	Disulfide bond	36 ↔ 55		By similarity
	Disulfide bond	40 ↔ 57		By similarity

Sequences

	Sequence		Length	Mass (Da)
	P0C908 [UniParc]. Last modified April 14, 2009. Version 1. Checksum: FEE2327C83D2C862	FASTA	59	6,402
	10 20 30 40 50 MKVFFAVLIA LFVCSMVIGI HGGVPINVKC RGSRDCLDPC KKAGMRFGKC INSKCHCTP

References

[1]

"Isolation of the first toxin from the scorpion Buthus occitanus israelis showing preference for Shaker potassium channels." Kozminsky-Atias A., Somech E., Zilberberg N. FEBS Lett. 581:2478-2484(2007) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 23-59, FUNCTION, MASS SPECTROMETRY. Tissue: Venom and Venom gland.

Cross-references

3D structure databases
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
Gene3D	3.30.30.10. 1 hit.
InterPro	IPR003614. Scorpion_toxin-like. IPR001947. Scorpion_toxinS_K_inh. [Graphical view]
Pfam	PF00451. Toxin_2. 1 hit. [Graphical view]
PRINTS	PR00286. CHARYBDTOXIN.
ProDom	PD003586. Scorpion_toxinS. 1 hit. [Graphical view] [Entries sharing at least one domain]
SUPFAM	SSF57095. SSF57095. 1 hit.
PROSITE	PS01138. SCORP_SHORT_TOXIN. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

KAX3A_BUTOS

Accession

Primary (citable) accession number: P0C908

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 14, 2009
Last sequence update:	April 14, 2009
Last modified:	May 1, 2013
This is version 9 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program