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Q86W47 (KCMB4_HUMAN) Reviewed, UniProtKB/Swiss-Prot

Last modified July 9, 2014. Version 92. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (5) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Calcium-activated potassium channel subunit beta-4
Alternative name(s):
BK channel subunit beta-4
Short name=BKbeta4
Short name=Hbeta4
Calcium-activated potassium channel, subfamily M subunit beta-4
Charybdotoxin receptor subunit beta-4
K(VCA)beta-4
Maxi K channel subunit beta-4
Slo-beta-4
Gene names
Name:KCNMB4
OrganismHomo sapiens (Human) [Reference proteome]
Taxonomic identifier9606 [NCBI]
Taxonomic lineageEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo

Protein attributes

Sequence length210 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Decreases the gating kinetics and calcium sensitivity of the KCNMA1 channel, but with fast deactivation kinetics. May decrease KCNMA1 channel openings at low calcium concentrations but increases channel openings at high calcium concentrations. Makes KCNMA1 channel resistant to 100 nM charybdotoxin (CTX) toxin concentrations. Ref.1 Ref.2 Ref.3

Subunit structure

Interacts with KCNMA1 tetramer. There are probably 4 molecules of KCMNB4 per KCNMA1 tetramer. Ref.3 Ref.4

Subcellular location

Membrane; Multi-pass membrane protein.

Tissue specificity

Predominantly expressed in brain. In brain, it is expressed in the cerebellum, cerebral cortex, medulla, spinal cord, occipital pole, frontal lobe, temporal lobe, putamen, amygdala, caudate nucleus, corpus callosum, hippocampus, substantia nigra and thalamus. Weakly or not expressed in other tissues. Ref.2 Ref.3

Domain

Resistance to charybdotoxin (CTX) toxin is mediated by the extracellular domain.

Post-translational modification

Phosphorylated. Phosphorylation modulates its effect on KCNMA1 activation kinetics. Ref.6

N-glycosylated. A highly glycosylated form is promoted by KCNMA1. Glycosylation, which is not required for the interaction with KCNMA1 and subcellular location, increases protection against charybdotoxin. Ref.1 Ref.7

Miscellaneous

Treatment with okadaic acid reduces its effect on KCNMA1.

Sequence similarities

Belongs to the KCNMB (TC 8.A.14.1) family. KCNMB4 subfamily. [View classification]

Ontologies

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 210210Calcium-activated potassium channel subunit beta-4
PRO_0000187055

Regions

Topological domain1 – 1919Cytoplasmic Potential
Transmembrane20 – 4021Helical; Name=1; Potential
Topological domain41 – 167127Extracellular Potential
Transmembrane168 – 18821Helical; Name=2; Potential
Topological domain189 – 21022Cytoplasmic Potential

Amino acid modifications

Glycosylation531N-linked (GlcNAc...)
Glycosylation901N-linked (GlcNAc...)

Natural variations

Natural variant1991V → I. Ref.1
VAR_018178

Experimental info

Mutagenesis111T → A: Suppresses the effect of okadaic acid and increases activation time constant; when associated with A-17 and A-210. Ref.6
Mutagenesis111T → D: Suppresses its effect on KCNMA1 channel activation and on deactivation kinetics; when associated with E-17 and E-210. Ref.6
Mutagenesis171S → A: Suppresses the effect of okadaic acid and increases activation time constant; when associated with A-11 and A-210. Ref.6
Mutagenesis171S → E: Suppresses its effect on KCNMA1 channel activation and on deactivation kinetics; when associated with D-11 and E-210. Ref.6
Mutagenesis531N → A: Loss of N-glycosylation and reduced protection against charybdotoxin; when associated with A-90. Ref.7
Mutagenesis901N → A: Loss of N-glycosylation and reduced protection against charybdotoxin; when associated with A-53. Ref.7
Mutagenesis2101S → A: Suppresses the effect of okadaic acid and increases activation time constant; when associated with A-11 and A-17. Ref.6
Mutagenesis2101S → E: Suppresses its effect on KCNMA1 channel activation and on deactivation kinetics; when associated with D-11 and E-17. Ref.6

Sequences

Sequence LengthMass (Da)Tools
Q86W47 [UniParc].

Last modified March 1, 2004. Version 2.
Checksum: A59D56DD034F027A

FASTA21023,949
        10         20         30         40         50         60 
MAKLRVAYEY TEAEDKSIRL GLFLIISGVV SLFIFGFCWL SPALQDLQAT EANCTVLSVQ 

        70         80         90        100        110        120 
QIGEVFECTF TCGADCRGTS QYPCVQVYVN NSESNSRALL HSDEHQLLTN PKCSYIPPCK 

       130        140        150        160        170        180 
RENQKNLESV MNWQQYWKDE IGSQPFTCYF NQHQRPDDVL LHRTHDEIVL LHCFLWPLVT 

       190        200        210 
FVVGVLIVVL TICAKSLAVK AEAMKKRKFS 

« Hide

References

« Hide 'large scale' references
[1]"A neuronal beta subunit (KCNMB4) makes the large conductance, voltage- and Ca2+-activated K+ channel resistant to charybdotoxin and iberiotoxin."
Meera P., Wallner M., Toro L.
Proc. Natl. Acad. Sci. U.S.A. 97:5562-5567(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, GLYCOSYLATION, VARIANT ILE-199.
[2]"hKCNMB3 and hKCNMB4, cloning and characterization of two members of the large-conductance calcium-activated potassium channel beta subunit family."
Behrens R., Nolting A., Reimann F., Schwarz M., Waldschuetz R., Pongs O.
FEBS Lett. 474:99-106(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, TISSUE SPECIFICITY.
[3]"Cloning and functional characterization of novel large conductance calcium-activated potassium channel beta subunits, hKCNMB3 and hKCNMB4."
Brenner R., Jegla T.J., Wickenden A., Liu Y., Aldrich R.W.
J. Biol. Chem. 275:6453-6461(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, INTERACTION WITH KCNMA1, TISSUE SPECIFICITY.
[4]"A novel nervous system beta subunit that downregulates human large conductance calcium-dependent potassium channels."
Weiger T.M., Holmqvist M.H., Levitan I.B., Clark F.T., Sprague S., Huang W.-J., Ge P., Wang C., Lawson D., Jurman M.E., Glucksmann M.A., Silos-Santiago I., DiStefano P.S., Curtis R.
J. Neurosci. 20:3563-3570(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], INTERACTION WITH KCNMA1.
Tissue: CNS.
[5]"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
The MGC Project Team
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
Tissue: Eye and Lymph.
[6]"Phosphorylation-dependent functional coupling of hSlo calcium-dependent potassium channel and its hbeta 4 subunit."
Jin P., Weiger T.M., Wu Y., Levitan I.B.
J. Biol. Chem. 277:10014-10020(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: PHOSPHORYLATION, MUTAGENESIS OF THR-11; SER-17 AND SER-210.
[7]"Reciprocal modulation between the alpha and beta 4 subunits of hSlo calcium-dependent potassium channels."
Jin P., Weiger T.M., Levitan I.B.
J. Biol. Chem. 277:43724-43729(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: GLYCOSYLATION, MUTAGENESIS OF ASN-53 AND ASN-90.
[8]"New disguises for an old channel: MaxiK channel beta-subunits."
Orio P., Rojas P., Ferreira G., Latorre R.
News Physiol. Sci. 17:156-161(2002) [PubMed] [Europe PMC] [Abstract]
Cited for: REVIEW.
+Additional computationally mapped references.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AF160967 mRNA. Translation: AAF69805.1.
AF170917 mRNA. Translation: AAF89699.1.
AF207992 mRNA. Translation: AAF28333.1.
AF215891 mRNA. Translation: AAF75596.1.
BC042446 mRNA. Translation: AAH42446.2.
BC050621 mRNA. Translation: AAH50621.2.
CCDSCCDS8997.1.
RefSeqNP_055320.4. NM_014505.5.
UniGeneHs.525529.

3D structure databases

ProteinModelPortalQ86W47.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

STRING9606.ENSP00000258111.

PTM databases

PhosphoSiteQ86W47.

Polymorphism databases

DMDM46395791.

Proteomic databases

PaxDbQ86W47.
PRIDEQ86W47.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblENST00000258111; ENSP00000258111; ENSG00000135643.
GeneID27345.
KEGGhsa:27345.
UCSCuc001svx.3. human.

Organism-specific databases

CTD27345.
GeneCardsGC12P070760.
HGNCHGNC:6289. KCNMB4.
MIM605223. gene.
neXtProtNX_Q86W47.
PharmGKBPA30069.
GenAtlasSearch...

Phylogenomic databases

eggNOGNOG83271.
HOGENOMHOG000113205.
HOVERGENHBG052224.
InParanoidQ86W47.
KOK04941.
OMAHEAPRKE.
OrthoDBEOG77WWDC.
PhylomeDBQ86W47.
TreeFamTF328589.

Enzyme and pathway databases

ReactomeREACT_13685. Neuronal System.
REACT_604. Hemostasis.

Gene expression databases

BgeeQ86W47.
CleanExHS_KCNMB4.
GenevestigatorQ86W47.

Family and domain databases

InterProIPR003930. K_chnl_Ca-activ_BK_bsu.
[Graphical view]
PANTHERPTHR10258. PTHR10258. 1 hit.
PfamPF03185. CaKB. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

ChiTaRSKCNMB4. human.
GeneWikiKCNMB4.
GenomeRNAi27345.
NextBio50430.
PROQ86W47.
SOURCESearch...

Entry information

Entry nameKCMB4_HUMAN
AccessionPrimary (citable) accession number: Q86W47
Secondary accession number(s): Q8IVR3, Q9NPA4, Q9P0G5
Entry history
Integrated into UniProtKB/Swiss-Prot: April 13, 2004
Last sequence update: March 1, 2004
Last modified: July 9, 2014
This is version 92 of the entry and version 2 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Relevant documents

SIMILARITY comments

Index of protein domains and families

MIM cross-references

Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot

Human polymorphisms and disease mutations

Index of human polymorphisms and disease mutations

Human entries with polymorphisms or disease mutations

List of human entries with polymorphisms or disease mutations

Human chromosome 12

Human chromosome 12: entries, gene names and cross-references to MIM