Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Calcium-activated potassium channel subunit beta-1

Gene

KCNMB1

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

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. Increases the apparent Ca2+/voltage sensitivity of the KCNMA1 channel. It also modifies KCNMA1 channel kinetics and alters its pharmacological properties. It slows down the activation and the deactivation kinetics of the channel. Acts as a negative regulator of smooth muscle contraction by enhancing the calcium sensitivity to KCNMA1. Its presence is also a requirement for internal binding of the KCNMA1 channel opener dehydrosoyasaponin I (DHS-1) triterpene glycoside and for external binding of the agonist hormone 17-beta-estradiol (E2). Increases the binding activity of charybdotoxin (CTX) toxin to KCNMA1 peptide blocker by increasing the CTX association rate and decreasing the dissociation rate.

GO - Molecular functioni

  1. calcium-activated potassium channel activity Source: ProtInc
  2. potassium channel regulator activity Source: ProtInc

GO - Biological processi

  1. blood coagulation Source: Reactome
  2. detection of calcium ion Source: GO_Central
  3. potassium ion transmembrane transport Source: GOC
  4. potassium ion transport Source: ProtInc
  5. synaptic transmission Source: Reactome
Complete GO annotation...

Keywords - Molecular functioni

Ion channel

Keywords - Biological processi

Ion transport, Transport

Enzyme and pathway databases

ReactomeiREACT_23767. cGMP effects.
REACT_75896. Ca2+ activated K+ channels.

Protein family/group databases

TCDBi8.A.14.1.2. the ca(2+)-activated k(+) channel auxiliary subunit slowpoke- (slo) family.

Names & Taxonomyi

Protein namesi
Recommended name:
Calcium-activated potassium channel subunit beta-1
Alternative name(s):
BK channel subunit beta-1
Short name:
BKbeta
Short name:
BKbeta1
Short name:
Hbeta1
Calcium-activated potassium channel, subfamily M subunit beta-1
Short name:
Calcium-activated potassium channel subunit beta
Charybdotoxin receptor subunit beta-1
K(VCA)beta-1
Maxi K channel subunit beta-1
Slo-beta-1
Short name:
Slo-beta
Gene namesi
Name:KCNMB1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 5

Organism-specific databases

HGNCiHGNC:6285. KCNMB1.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini2 – 1817CytoplasmicSequence AnalysisAdd
BLAST
Transmembranei19 – 3921Helical; Name=1Sequence AnalysisAdd
BLAST
Topological domaini40 – 157118ExtracellularSequence AnalysisAdd
BLAST
Transmembranei158 – 17821Helical; Name=2Sequence AnalysisAdd
BLAST
Topological domaini179 – 19113CytoplasmicSequence AnalysisAdd
BLAST

GO - Cellular componenti

  1. plasma membrane Source: Reactome
  2. voltage-gated potassium channel complex Source: GO_Central
Complete GO annotation...

Keywords - Cellular componenti

Membrane

Pathology & Biotechi

Organism-specific databases

MIMi608622. phenotype.
PharmGKBiPA221.

Chemistry

DrugBankiDB01110. Miconazole.
DB00721. Procaine.

Polymorphism and mutation databases

DMDMi292495100.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Initiator methioninei1 – 11RemovedBy similarity
Chaini2 – 191190Calcium-activated potassium channel subunit beta-1PRO_0000187046Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Glycosylationi80 – 801N-linked (GlcNAc...)Sequence Analysis
Glycosylationi142 – 1421N-linked (GlcNAc...)Sequence Analysis

Post-translational modificationi

N-glycosylated.1 Publication

Keywords - PTMi

Glycoprotein

Proteomic databases

PRIDEiQ16558.

PTM databases

PhosphoSiteiQ16558.

Expressioni

Tissue specificityi

Abundantly expressed in smooth muscle. Low levels of expression in most other tissues. Within the brain, relatively high levels found in hippocampus and corpus callosum.

Gene expression databases

BgeeiQ16558.
CleanExiHS_KCNMB1.
GenevestigatoriQ16558.

Organism-specific databases

HPAiHPA020435.

Interactioni

Subunit structurei

Interacts with KCNMA1 tetramer. There are probably 4 molecules of KCMNB1 per KCNMA1 tetramer.

Protein-protein interaction databases

BioGridi109980. 4 interactions.
IntActiQ16558. 1 interaction.
MINTiMINT-1470084.
STRINGi9606.ENSP00000274629.

Structurei

3D structure databases

ProteinModelPortaliQ16558.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Sequence similaritiesi

Keywords - Domaini

Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiNOG40171.
GeneTreeiENSGT00390000015997.
HOVERGENiHBG052223.
InParanoidiQ16558.
KOiK04937.
OMAiIIAMVKI.
OrthoDBiEOG77WWDC.
PhylomeDBiQ16558.
TreeFamiTF328589.

Family and domain databases

InterProiIPR003930. K_chnl_Ca-activ_BK_bsu.
[Graphical view]
PANTHERiPTHR10258. PTHR10258. 1 hit.
PfamiPF03185. CaKB. 1 hit.
[Graphical view]
PRINTSiPR01450. BKCHANNELB.

Sequences (2)i

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q16558-1) [UniParc]FASTAAdd to basket

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

« Hide

        10         20         30         40         50
MVKKLVMAQK RGETRALCLG VTMVVCAVIT YYILVTTVLP LYQKSVWTQE
60 70 80 90 100
SKCHLIETNI RDQEELKGKK VPQYPCLWVN VSAAGRWAVL YHTEDTRDQN
110 120 130 140 150
QQCSYIPGSV DNYQTARADV EKVRAKFQEQ QVFYCFSAPR GNETSVLFQR
160 170 180 190
LYGPQALLFS LFWPTFLLTG GLLIIAMVKS NQYLSILAAQ K
Length:191
Mass (Da):21,797
Last modified:March 23, 2010 - v5
Checksum:i547432FF194E770D
GO
Isoform 2 (identifier: Q16558-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     103-130: CSYIPGSVDNYQTARADVEKVRAKFQEQ → VLNWRDGDTSLYPCQVCEPVPNCPCPRG
     131-191: Missing.

Note: No experimental confirmation available.

Show »
Length:130
Mass (Da):14,858
Checksum:i2E612865F4130EEE
GO

Polymorphismi

Genetic variation in KCNMB1 can influence the severity of diastolic hypertension.

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti65 – 651E → K Has a protective effect against diastolic hypertension. 1 Publication
Corresponds to variant rs11739136 [ dbSNP | Ensembl ].
VAR_019325
Natural varianti110 – 1101V → L.
Corresponds to variant rs2301149 [ dbSNP | Ensembl ].
VAR_047009

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei103 – 13028CSYIP…KFQEQ → VLNWRDGDTSLYPCQVCEPV PNCPCPRG in isoform 2. 1 PublicationVSP_009822Add
BLAST
Alternative sequencei131 – 19161Missing in isoform 2. 1 PublicationVSP_009823Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U25138 mRNA. Translation: AAB02394.1.
U38907 mRNA. Translation: AAA81327.1.
U42600 mRNA. Translation: AAB16827.1.
U42601 Genomic DNA. Translation: AAB16825.1.
U42603, U42602 Genomic DNA. Translation: AAB16826.1.
U61536 mRNA. Translation: AAB61396.1.
U61537 Genomic DNA. Translation: AAB61397.1.
AF026002 mRNA. Translation: AAB88805.1.
AY044441 mRNA. Translation: AAK95827.1.
AY515264 mRNA. Translation: AAS20193.1.
AK313979 mRNA. Translation: BAG36693.1.
CH471062 Genomic DNA. Translation: EAW61474.1.
BC025707 mRNA. Translation: AAH25707.1.
CCDSiCCDS4373.1. [Q16558-1]
PIRiS68842.
RefSeqiNP_004128.1. NM_004137.3. [Q16558-1]
UniGeneiHs.484099.
Hs.744947.

Genome annotation databases

EnsembliENST00000274629; ENSP00000274629; ENSG00000145936. [Q16558-1]
ENST00000521859; ENSP00000427940; ENSG00000145936. [Q16558-2]
GeneIDi3779.
KEGGihsa:3779.
UCSCiuc003maq.2. human. [Q16558-1]
uc003mar.4. human. [Q16558-2]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U25138 mRNA. Translation: AAB02394.1.
U38907 mRNA. Translation: AAA81327.1.
U42600 mRNA. Translation: AAB16827.1.
U42601 Genomic DNA. Translation: AAB16825.1.
U42603, U42602 Genomic DNA. Translation: AAB16826.1.
U61536 mRNA. Translation: AAB61396.1.
U61537 Genomic DNA. Translation: AAB61397.1.
AF026002 mRNA. Translation: AAB88805.1.
AY044441 mRNA. Translation: AAK95827.1.
AY515264 mRNA. Translation: AAS20193.1.
AK313979 mRNA. Translation: BAG36693.1.
CH471062 Genomic DNA. Translation: EAW61474.1.
BC025707 mRNA. Translation: AAH25707.1.
CCDSiCCDS4373.1. [Q16558-1]
PIRiS68842.
RefSeqiNP_004128.1. NM_004137.3. [Q16558-1]
UniGeneiHs.484099.
Hs.744947.

3D structure databases

ProteinModelPortaliQ16558.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi109980. 4 interactions.
IntActiQ16558. 1 interaction.
MINTiMINT-1470084.
STRINGi9606.ENSP00000274629.

Chemistry

ChEMBLiCHEMBL3038495.
DrugBankiDB01110. Miconazole.
DB00721. Procaine.

Protein family/group databases

TCDBi8.A.14.1.2. the ca(2+)-activated k(+) channel auxiliary subunit slowpoke- (slo) family.

PTM databases

PhosphoSiteiQ16558.

Polymorphism and mutation databases

DMDMi292495100.

Proteomic databases

PRIDEiQ16558.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000274629; ENSP00000274629; ENSG00000145936. [Q16558-1]
ENST00000521859; ENSP00000427940; ENSG00000145936. [Q16558-2]
GeneIDi3779.
KEGGihsa:3779.
UCSCiuc003maq.2. human. [Q16558-1]
uc003mar.4. human. [Q16558-2]

Organism-specific databases

CTDi3779.
GeneCardsiGC05M169737.
HGNCiHGNC:6285. KCNMB1.
HPAiHPA020435.
MIMi603951. gene.
608622. phenotype.
neXtProtiNX_Q16558.
PharmGKBiPA221.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG40171.
GeneTreeiENSGT00390000015997.
HOVERGENiHBG052223.
InParanoidiQ16558.
KOiK04937.
OMAiIIAMVKI.
OrthoDBiEOG77WWDC.
PhylomeDBiQ16558.
TreeFamiTF328589.

Enzyme and pathway databases

ReactomeiREACT_23767. cGMP effects.
REACT_75896. Ca2+ activated K+ channels.

Miscellaneous databases

GeneWikiiKCNMB1.
GenomeRNAii3779.
NextBioi14829.
PROiQ16558.
SOURCEiSearch...

Gene expression databases

BgeeiQ16558.
CleanExiHS_KCNMB1.
GenevestigatoriQ16558.

Family and domain databases

InterProiIPR003930. K_chnl_Ca-activ_BK_bsu.
[Graphical view]
PANTHERiPTHR10258. PTHR10258. 1 hit.
PfamiPF03185. CaKB. 1 hit.
[Graphical view]
PRINTSiPR01450. BKCHANNELB.
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "A calcium switch for the functional coupling between alpha (hslo) and beta subunits (KV,Ca beta) of maxi K channels."
    Meera P., Wallner M., Jiang Z., Toro L.
    FEBS Lett. 382:84-88(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
    Tissue: Uterus.
  2. "Phenotypic alteration of a human BK (hSlo) channel by hSlobeta subunit coexpression: changes in blocker sensitivity, activation/relaxation and inactivation kinetics, and protein kinase A modulation."
    Dworetzky S.I., Boissard C.G., Lum-Ragan J.T., McKay M.C., Post-Munson D.J., Trojnacki J.T., Chang C.P., Gribkoff V.K.
    J. Neurosci. 16:4543-4550(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
    Tissue: Uterus.
  3. "Cloning, expression, and distribution of a Ca(2+)-activated K+ channel beta-subunit from human brain."
    Tseng-Crank J., Godinot N., Johansen T.E., Ahring P.K., Strobaek D., Mertz R., Foster C.D., Olesen S.P., Reinhart P.H.
    Proc. Natl. Acad. Sci. U.S.A. 93:9200-9205(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORM 1).
    Tissue: Brain.
  4. "Sequence of the gene encoding the beta subunit of a human, large-conductance, calcium-activate, K+ channel."
    Folander K., Biazzo D., Swanson R.
    Submitted (JUN-1997) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA] (ISOFORM 1).
    Tissue: Aortic smooth muscle.
  5. "Identification of potassium channels in human lens epithelium."
    Rae J.L., Shepard A.R.
    (In) Civan M.M. (eds.); The eye's aqueous humor, from secretion to glaucoma, pp.69-104, Academic Press, San Diego (1998)
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
  6. "Calcium-activated potassium channel expression in human myometrium: effect of pregnancy."
    Mazzone J.N., Kaiser R.A., Buxton I.L.O.
    Proc. West. Pharmacol. Soc. 45:184-186(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
    Tissue: Myometrium.
  7. "Role of the BK-beta1 subunit in human mesangial cells."
    Pluznick J.L., Sansom S.C.
    Submitted (DEC-2003) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
  8. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Cervix.
  9. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  10. "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] (ISOFORM 2).
    Tissue: Pancreas.
  11. "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: GLYCOSYLATION.
  12. "Acute activation of Maxi-K channels (hSlo) by estradiol binding to the beta subunit."
    Valverde M.A., Rojas P., Amigo J., Cosmelli D., Orio P., Bahamonde M.I., Mann G.E., Vergara C., Latorre R.
    Science 285:1929-1931(1999) [PubMed] [Europe PMC] [Abstract]
    Cited for: BINDING TO E2.
  13. "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.
  14. "Gain-of-function mutation in the KCNMB1 potassium channel subunit is associated with low prevalence of diastolic hypertension."
    Fernandez-Fernandez J.M., Tomas M., Vazquez E., Orio P., Latorre R., Senti M., Marrugat J., Valverde M.A.
    J. Clin. Invest. 113:1032-1039(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: VARIANT LYS-65.

Entry informationi

Entry nameiKCMB1_HUMAN
AccessioniPrimary (citable) accession number: Q16558
Secondary accession number(s): O00707
, O00708, P78475, Q53YR0, Q8TAX3, Q93005
Entry historyi
Integrated into UniProtKB/Swiss-Prot: November 1, 1997
Last sequence update: March 23, 2010
Last modified: March 4, 2015
This is version 127 of the entry and version 5 of the sequence. [Complete history]
Entry statusiReviewed (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.

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. Human chromosome 5
    Human chromosome 5: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. SIMILARITY comments
    Index of protein domains and families

External Data

Dasty 3

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into Uniref entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.