P15223 (SCX1_CENNO) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Toxin Cn1 Alternative name(s): Toxin II.14 Short name=Toxin 1
Organism	Centruroides noxius (Mexican scorpion)
Taxonomic identifier	6878 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Ecdysozoa › Panarthropoda › Arthropoda › Chelicerata › Arachnida › Scorpiones › Buthida › Buthoidea › Buthidae › Centruroides

Protein attributes

Sequence length	86 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	Beta toxins bind voltage-independently at site-4 of sodium channels (Nav) and shift the voltage of activation toward more negative potentials thereby affecting sodium channel activation and promoting spontaneous and repetitive firing By similarity.
Subcellular location	Secreted.
Tissue specificity	Expressed by the venom gland.
Sequence similarities	Belongs to the long (4 C-C) scorpion toxin superfamily. Sodium channel inhibitor family. Beta subfamily.

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ion channel impairing toxin Neurotoxin Sodium channel inhibitor Toxin
PTM	Amidation Disulfide bond
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological_process	defense response Inferred from electronic annotation. Source: InterPro
Cellular_component	extracellular region Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular_function	sodium 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 – 19	19	Ref.2
	Chain	20 – 84	65	Toxin Cn1		PRO_0000035279
Amino acid modifications
	Modified residue	84	1	Serine amide Ref.1
	Disulfide bond	30 ↔ 83		By similarity
	Disulfide bond	34 ↔ 59		By similarity
	Disulfide bond	43 ↔ 64		By similarity
	Disulfide bond	47 ↔ 66		By similarity
Experimental info
	Sequence conflict	79	1	P → T AA sequence Ref.2

Sequences

	Sequence		Length	Mass (Da)
	P15223 [UniParc]. Last modified December 15, 1998. Version 3. Checksum: AB8C1EA742F17222	FASTA	86	9,586
	10 20 30 40 50 60 MNSLLMITAC FVLIGTVWAK DGYLVDAKGC KKNCYKLGKN DYCNRECRMK HRGGSYGYCY 70 80 GFGCYCEGLS DSTPTWPLPN KTCSGK

References

[1]	"Cloning and characterization of the cDNAs encoding Na+ channel-specific toxins 1 and 2 of the scorpion Centruroides noxius Hoffmann." Vazquez A., Tapia J.V., Eliason W.K., Martin B.M., Lebreton F., Delepierre M., Possani L.D., Becerril B. Toxicon 33:1161-1170(1995) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], AMIDATION AT SER-84. Tissue: Venom gland.
[2]	"Scorpion toxins from Centruroides noxius and Tityus serrulatus. Primary structures and sequence comparison by metric analysis." Possani L.D., Martin B.M., Svendsen I., Rode G.S., Erickson B.W. Biochem. J. 229:739-750(1985) [PubMed] [Europe PMC] [Abstract] Cited for: PROTEIN SEQUENCE OF 20-84. Tissue: Venom.

Cross-references

Sequence databases
EMBL GenBank DDBJ	S81093 mRNA. Translation: AAB36085.2.
PIR	S32789.
3D structure databases
ProteinModelPortal	P15223.
SMR	P15223. Positions 20-83.
ModBase	Search...
Protocols and materials databases
StructuralBiologyKnowledgebase	Search...
Family and domain databases
Gene3D	3.30.30.10. 1 hit.
InterPro	IPR003614. Scorpion_toxin-like. IPR018218. Scorpion_toxinL. IPR002061. Scorpion_toxinL/defesin. [Graphical view]
Pfam	PF00537. Toxin_3. 1 hit. [Graphical view]
PRINTS	PR00285. SCORPNTOXIN.
SMART	SM00505. Knot1. 1 hit. [Graphical view]
SUPFAM	SSF57095. SSF57095. 1 hit.
ProtoNet	Search...

Entry information

Entry name

SCX1_CENNO

Accession

Primary (citable) accession number: P15223
Secondary accession number(s): Q26460

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 1, 1990
Last sequence update:	December 15, 1998
Last modified:	May 1, 2013
This is version 80 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program