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P45639 (SCXL_LEIQU) Reviewed, UniProtKB/Swiss-Prot

Last modified December 11, 2013. Version 68. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (2) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Web links·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Chlorotoxin

Short name=CTX
Short name=ClTx
OrganismLeiurus quinquestriatus quinquestriatus (Egyptian scorpion) (Deathstalker scorpion)
Taxonomic identifier6885 [NCBI]
Taxonomic lineageEukaryotaMetazoaEcdysozoaArthropodaChelicerataArachnidaScorpionesButhidaButhoideaButhidaeLeiurus

Protein attributes

Sequence length36 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Chloride channel ligand. Blocks small-conductance chloride channels.

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.

Pharmaceutical use

Is under phase II clinical trial by Sinai Medical Center and TransMolecular under the name TM-601. It crosses blood-brain and tissue barriers and binds to malignant brain tumor cells without affecting healthy tissue. Radioiodinated TM-601 is used to treat malignant glioma.

Sequence similarities

Belongs to the short scorpion toxin superfamily. Chloride channel inhibitor family.

Ontologies

Keywords
   Cellular componentSecreted
   DomainKnottin
   Molecular functionChloride channel inhibitor
Ion channel impairing toxin
Neurotoxin
Toxin
   PTMDisulfide bond
   Technical term3D-structure
Direct protein sequencing
Pharmaceutical
Gene Ontology (GO)
   Biological_processdefense response

Inferred from electronic annotation. Source: InterPro

pathogenesis

Inferred from electronic annotation. Source: InterPro

   Cellular_componentextracellular region

Inferred from electronic annotation. Source: UniProtKB-SubCell

   Molecular_functionchloride channel inhibitor activity

Inferred from electronic annotation. Source: UniProtKB-KW

Complete GO annotation...

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Peptide1 – 3636Chlorotoxin
PRO_0000044941

Amino acid modifications

Disulfide bond2 ↔ 19 Ref.4
Disulfide bond5 ↔ 28 Ref.4
Disulfide bond16 ↔ 33 Ref.4
Disulfide bond20 ↔ 35 Ref.4

Secondary structure

.......... 36
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
P45639 [UniParc].

Last modified November 1, 1995. Version 1.
Checksum: 14A9F57559C6E92A

FASTA364,005
        10         20         30 
MCMPCFTTDH QMARKCDDCC GGKGRGKCYG PQCLCR 

« Hide

References

[1]"Purification and characterization of chlorotoxin, a chloride channel ligand from the venom of the scorpion."
Debin J.A., Maggio J.E., Strichartz G.R.
Am. J. Physiol. 264:C361-C369(1993) [PubMed] [Europe PMC] [Abstract]
Cited for: PROTEIN SEQUENCE.
Tissue: Venom.
[2]"Use of chlorotoxin for targeting of primary brain tumors."
Soroceanu L., Gillespie Y., Khazaeli M.B., Sontheimer H.
Cancer Res. 58:4871-4879(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: POTENTIAL THERAPEUTIC USAGE.
[3]"Phase I single-dose study of intracavitary-administered iodine-131-TM-601 in adults with recurrent high-grade glioma."
Mamelak A.N., Rosenfeld S., Bucholz R., Raubitschek A., Nabors L.B., Fiveash J.B., Shen S., Khazaeli M.B., Colcher D., Liu A., Osman M., Guthrie B., Schade-Bijur S., Hablitz D.M., Alvarez V.L., Gonda M.A.
J. Clin. Oncol. 24:3644-3650(2006) [PubMed] [Europe PMC] [Abstract]
Cited for: POTENTIAL THERAPEUTIC USAGE IN TREATMENT OF GLIOMA.
[4]"NMR sequential assignments and solution structure of chlorotoxin, a small scorpion toxin that blocks chloride channels."
Lippens G., Najib J., Wodak S.J., Tartar A.
Biochemistry 34:13-21(1995) [PubMed] [Europe PMC] [Abstract]
Cited for: STRUCTURE BY NMR, DISULFIDE BONDS.

Web resources

Wikipedia

Chlorotoxin entry

Cross-references

Sequence databases

PIRA48850.

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1CHLNMR-A1-36[»]
ProteinModelPortalP45639.
SMRP45639. Positions 1-36.
ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Family and domain databases

InterProIPR003614. Scorpion_toxin-like.
IPR007958. Scorpion_toxinS_Cl_inh.
[Graphical view]
PfamPF05294. Toxin_5. 1 hit.
[Graphical view]
SUPFAMSSF57095. SSF57095. 1 hit.
PROSITEPS51200. SHORT_SCORPION_CHLORIDE. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

EvolutionaryTraceP45639.

Entry information

Entry nameSCXL_LEIQU
AccessionPrimary (citable) accession number: P45639
Entry history
Integrated into UniProtKB/Swiss-Prot: November 1, 1995
Last sequence update: November 1, 1995
Last modified: December 11, 2013
This is version 68 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programAnimal Toxin Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families

PDB cross-references

Index of Protein Data Bank (PDB) cross-references