C1J5M6 (CM3B_CONBU) Reviewed, UniProtKB/Swiss-Prot

Names and origin

Protein names	Recommended name: Mu-conotoxin BuIIIB Alternative name(s): Conotoxin Bu16
Organism	Conus bullatus (Bubble cone)
Taxonomic identifier	89438 [NCBI]
Taxonomic lineage	cellular organisms › Eukaryota › Opisthokonta › Metazoa › Eumetazoa › Bilateria › Protostomia › Lophotrochozoa › Mollusca › Gastropoda › Caenogastropoda › Hypsogastropoda › Neogastropoda › Conoidea › Conidae › Conus

Protein attributes

Sequence length	78 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	Mu-conotoxins block voltage-gated sodium channels. Extremely potent inhibitor of Nav1.4/SCN4A. The inhibition is very slowly reversible. Ref.1
Subcellular location	Secreted By similarity.
Tissue specificity	Expressed by the venom duct.
Domain	The cysteine framework is III (CC-C-C-CC). Classified in the M-5 branch, since 5 residues stand between the fourth and the fifth cysteine residues.
Sequence similarities	Belongs to the conotoxin M superfamily.

Ontologies

Keywords
Cellular component	Secreted
Domain	Signal
Molecular function	Ion channel impairing toxin Neurotoxin Sodium channel inhibitor Toxin
PTM	Amidation Cleavage on pair of basic residues Disulfide bond
Technical term	3D-structure
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	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 – 22

22

Potential

Propeptide

23 – 51

29

By similarity

PRO_0000384433

Peptide

52 – 75

24

Mu-conotoxin BuIIIB

PRO_0000384434

Amino acid modifications

Modified residue

75

1

Cysteine amide By similarity

Disulfide bond

56 ↔ 68

By similarity

Disulfide bond

57 ↔ 74

By similarity

Disulfide bond

64 ↔ 75

By similarity

Secondary structure

1

.

.

.

.

.

.

.

78

Helix Strand Turn

Details...

Helix

54 – 57

4

Helix

60 – 62

3

Turn

63 – 65

3

Helix

66 – 71

6

Sequences

	Sequence		Length	Mass (Da)
	C1J5M6 [UniParc]. Last modified May 26, 2009. Version 1. Checksum: 907D09C9B4DE3164	FASTA	78	8,877
	10 20 30 40 50 60 MMSKLGVLLT ICLLLFPLFA LPQDGDQPAD RPAERMQDDI SSEQNPLLEK RVGERCCKNG 70 KRGCGRWCRD HSRCCGRR

References

[1]	"Pruning nature: biodiversity-derived discovery of novel sodium channel blocking conotoxins from Conus bullatus." Holford M., Zhang M.-M., Gowd K.H., Azam L., Green B.R., Watkins M., Ownby J.-P., Yoshikami D., Bulaj G., Olivera B.M. Toxicon 53:90-98(2009) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], SYNTHESIS OF 51-75, FUNCTION.
[2]	"Characterization of the Conus bullatus genome and its venom-duct transcriptome." Hu H., Bandyopadhyay P.K., Olivera B.M., Yandell M. BMC Genomics 12:60-75(2011) [PubMed] [Europe PMC] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 26-78. Tissue: Venom duct.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ

FJ240166 mRNA. Translation: ACO50771.1.

3D structure databases

PDBe
RCSB PDB
PDBj

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
2LO9	NMR	-	A	52-75	[»]
2LOC	NMR	-	A	54-75	[»]

ModBase

Search...

Protocols and materials databases

StructuralBiologyKnowledgebase

Search...

Organism-specific databases

ConoServer

3715. BuIIIB precursor.

Family and domain databases

InterPro

IPR004214. Conotoxin.
[Graphical view]

Pfam

PF02950. Conotoxin. 1 hit.
[Graphical view]

PROSITE

PS60013. MU_CONOTOXIN. False negative.
[Graphical view]

ProtoNet

Search...

Entry information

Entry name

CM3B_CONBU

Accession

Primary (citable) accession number: C1J5M6

Entry history

Integrated into UniProtKB/Swiss-Prot:	September 22, 2009
Last sequence update:	May 26, 2009
Last modified:	May 1, 2013
This is version 17 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation program

Animal Toxin Annotation Program