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P01521 (CA1_CONMA) Reviewed, UniProtKB/Swiss-Prot

Last modified July 24, 2013. Version 65. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | Third-party data text xml rdf/xml gff fasta
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Names and origin

Protein namesRecommended name:
Alpha-conotoxin MI

Short name=Alpha-MI
Short name=CtxMI
Alternative name(s):
M1
OrganismConus magus (Magus cone) (Magician's cone snail)
Taxonomic identifier6492 [NCBI]
Taxonomic lineageEukaryotaMetazoaLophotrochozoaMolluscaGastropodaCaenogastropodaHypsogastropodaNeogastropodaConoideaConidaeConus

Protein attributes

Sequence length14 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Alpha-conotoxins act on postsynaptic membranes, they bind to the nicotinic acetylcholine receptors (nAChR) and thus inhibit them. Blocks mammalian nAChR composed of alpha-1/delta subunits with high potency and alpha-1/gamma with a low potency. Ref.3

Subcellular location

Secreted.

Tissue specificity

Expressed by the venom duct.

Domain

The cysteine framework is I (CC-C-C).

Post-translational modification

Amidated; synthetic peptide with a C-terminus free is 6-fold less active than the amidated peptide.

Sequence similarities

Belongs to the conotoxin A superfamily.

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Peptide1 – 1414Alpha-conotoxin MI
PRO_0000044461

Amino acid modifications

Modified residue141Cysteine amide Ref.1
Disulfide bond3 ↔ 8 Ref.2
Disulfide bond4 ↔ 14 Ref.2

Experimental info

Mutagenesis21R → A: 4-fold loss of activity. Ref.3
Mutagenesis51H → A: 3-fold loss of activity. Ref.3
Mutagenesis61P → A: 73-fold loss of activity. Ref.3
Mutagenesis101K → A: 9-fold loss of activity. Ref.3
Mutagenesis111N → A: 3-fold loss of activity. Ref.3
Mutagenesis121Y → A: 8500-fold loss of activity. Ref.3
Mutagenesis121Y → H: 33-fold loss of activity. Ref.3
Mutagenesis121Y → M: 48-fold loss of activity. Ref.3
Mutagenesis121Y → W: 5-fold loss of activity. Ref.3
Mutagenesis131S → A: No loss of activity. Ref.3

Sequences

Sequence LengthMass (Da)Tools
P01521 [UniParc].

Last modified July 21, 1986. Version 1.
Checksum: DEEE91898BF5E5BD

FASTA141,499
        10 
GRCCHPACGK NYSC 

« Hide

References

[1]"Isolation and structure of a peptide toxin from the marine snail Conus magus."
McIntosh J.M., Cruz L.J., Hunkapiller M.W., Gray W.R., Olivera B.M.
Arch. Biochem. Biophys. 218:329-334(1982) [PubMed] [Europe PMC] [Abstract]
Cited for: PROTEIN SEQUENCE.
[2]"Conotoxin MI. Disulfide bonding and conformational states."
Gray W.R., Rivier J.E., Galyean R., Cruz L.J., Olivera B.M.
J. Biol. Chem. 258:12247-12251(1983) [PubMed] [Europe PMC] [Abstract]
Cited for: DISULFIDE BONDS.
[3]"Critical residues influence the affinity and selectivity of alpha-conotoxin MI for nicotinic acetylcholine receptors."
Jacobsen R.B., DelaCruz R.G., Grose J.H., McIntosh J.M., Yoshikami D., Olivera B.M.
Biochemistry 38:13310-13315(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, SYNTHESIS, MUTAGENESIS OF ARG-2; HIS-5; PRO-6; LYS-10; ASN-11; TYR-12 AND SER-13.

Cross-references

Sequence databases

PIRNTKN1M. A01784.

3D structure databases

ModBaseSearch...
MobiDBSearch...

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Organism-specific databases

ConoServer23. MI.

Family and domain databases

InterProIPR018072. Conotoxin_a-typ_CS.
[Graphical view]
PROSITEPS60014. ALPHA_CONOTOXIN. 1 hit.
[Graphical view]
ProtoNetSearch...

Entry information

Entry nameCA1_CONMA
AccessionPrimary (citable) accession number: P01521
Entry history
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 21, 1986
Last modified: July 24, 2013
This is version 65 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