P0C2P4 (VSTX2_GRARO) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Kappa-theraphotoxin-Gr2b Short name=Kappa-TRTX-Gr2b Alternative name(s): Voltage sensor toxin 2 Short name=VSTX2
Organism	Grammostola rosea (Chilean rose tarantula) (Grammostola spatulata)
Taxonomic identifier	432528 [NCBI]
Taxonomic lineage	Eukaryota › Metazoa › Arthropoda › Chelicerata › Arachnida › Araneae › Mygalomorphae › Theraphosidae › Grammostola

Protein attributes

Sequence length	32 AA.
Sequence status	Complete.
Protein existence	Evidence at protein level

General annotation (Comments)

Function	Binds the voltage-sensor domain of the potassium channel KvAP (from the archaeon Aeropyrum pernix) and affects channel gating. Ref.1
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland.
Domain	The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin By similarity.
Sequence similarities	Belongs to the phrixotoxin family.

Ontologies

Keywords
Cellular component	Secreted
Domain	Knottin
Molecular function	Ionic channel inhibitor Neurotoxin Potassium channel inhibitor Toxin
PTM	Disulfide bond
Technical term	Direct protein sequencing
Gene Ontology (GO)
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
	Peptide	1 – 32	32	Kappa-theraphotoxin-Gr2b		PRO_0000283770
Amino acid modifications
	Disulfide bond	2 ↔ 16		By similarity
	Disulfide bond	9 ↔ 21		By similarity
	Disulfide bond	15 ↔ 25		By similarity

Sequences

	Sequence		Length	Mass (Da)
	P0C2P4 [UniParc]. Last modified April 3, 2007. Version 1. Checksum: 7CE763EB84DE1AAC	FASTA	32	3,986
	10 20 30 YCQKWMWTCD EERKCCEGLV CRLWCKKKIE EG

References

[1]	"Localization of the voltage-sensor toxin receptor on KvAP." Ruta V., MacKinnon R. Biochemistry 43:10071-10079(2004) [PubMed: 15287735] [Abstract] Cited for: PROTEIN SEQUENCE, FUNCTION. Tissue: Venom.

Cross-references

3D structure databases
ProteinModelPortal	P0C2P4.
SMR	P0C2P4. Positions 1-30.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Organism-specific databases
ArachnoServer	AS000424. kappa-theraphotoxin-Gr2b.
Family and domain databases
ProtoNet	Search...

Entry information

Entry name

VSTX2_GRARO

Accession

Primary (citable) accession number: P0C2P4

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 3, 2007
Last sequence update:	April 3, 2007
Last modified:	November 16, 2011
This is version 14 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program