Reviewed, UniProtKB/Swiss-Prot Q28067 (KCMB1_BOVIN)

Names and origin

Protein names

Recommended name:
    Calcium-activated potassium channel subunit beta-1
Alternative name(s):
    Calcium-activated potassium channel, subfamily M subunit beta-1
      Short name=Calcium-activated potassium channel subunit beta
    Maxi K channel subunit beta-1
    BK channel subunit beta-1
      Short name=BKbeta1
      Short name=BKbeta
    K(VCA)beta-1
    Slo-beta-1
      Short name=Slo-beta
    Charybdotoxin receptor subunit beta-1

Gene names

Name:

KCNMB1

Organism

Bos taurus (Bovine)

Taxonomic identifier

9913 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Laurasiatheria › Cetartiodactyla › Ruminantia › Pecora › Bovidae › Bovinae › Bos

Protein attributes

Sequence length	191 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	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 By similarity.
Subunit structure	Interacts with KCNMA1 tetramer. There are probably 4 molecules of KCMNB1 per KCNMA1 tetramer By similarity.
Subcellular location	Membrane; Multi-pass membrane protein.
Post-translational modification	N-glycosylated By similarity.
Sequence similarities	Belongs to the KCNMB family.

Ontologies

Keywords
Biological process	Ion transport Transport
Cellular component	Membrane
Domain	Transmembrane
Molecular function	Ionic channel
PTM	Glycoprotein
Technical term	Direct protein sequencing
Gene Ontology (GO)
Biological process	potassium ion transport Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Initiator methionine	1	1	Removed Ref.1
	Chain	2 – 191	190	Calcium-activated potassium channel subunit beta-1		PRO_0000187044
Regions
	Topological domain	2 – 18	17	Cytoplasmic Potential
	Transmembrane	19 – 39	21	1 Potential
	Topological domain	40 – 157	118	Extracellular Potential
	Transmembrane	158 – 178	21	2 Potential
	Topological domain	179 – 191	13	Cytoplasmic Potential
Amino acid modifications
	Glycosylation	80	1	N-linked (GlcNAc...) Potential
	Glycosylation	142	1	N-linked (GlcNAc...) Potential

Sequences

	Sequence		Length	Mass (Da)
	Q28067-1 [UniParc]. Last modified January 23, 2007. Version 3. Checksum: 111C15E4A2B6B545	FASTA	191	21,957
	10 20 30 40 50 60 MGKKLVMAQR RGETRALCLG VAMVVGAVIT YYILGTTVLP LYQKSVWTQE STCHLIETNI 70 80 90 100 110 120 RDQEELEGKR VPQYPCLWVN VSSVGRWAVL YHTEDTRDQN HQCSYIPSSL DNYQVARADV 130 140 150 160 170 180 EKVRARFHEN QDFFCFSTTR ENETSVLYRR LYGPQSLLFS LFWPTFLLTG GLLIIVMVKI 190 NQSLSILAAQ R

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Primary sequence and immunological characterization of beta-subunit of high conductance Ca(2+)-activated K+ channel from smooth muscle." Knaus H.-G., Folander K., Garcia-Calvo M., Garcia M.L., Kaczorowski G.J., Smith M., Swanson R. J. Biol. Chem. 269:17274-17278(1994) [PubMed: 8006036] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA], PROTEIN SEQUENCE OF 2-29. Tissue: Aorta and Trachea.
[2]	NIH - Mammalian Gene Collection (MGC) project Submitted (JUN-2007) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA]. Strain: Hereford. Tissue: Uterus.

Cross-references

Sequence databases
EMBLGenBankDDBJ	L26101 mRNA. Translation: AAA21741.1. BC147983 mRNA. Translation: AAI47984.1.
IPI	IPI00697173.
PIR	A54165.
RefSeq	NP_001001141.1.
UniGene	Bt.62471
3D structure databases
ModBase	Search...
Genome annotation databases
Ensembl	ENSBTAG00000002985. Bos taurus. [Contig view]
GeneID	407176.
KEGG	bta:407176.
Phylogenomic databases
HOVERGEN	Q28067.
OMA	Q28067. WPTFLLT.
Family and domain databases
InterPro	IPR003930. K_chnl_Ca-activ_BK_bsu. [Graphical view]
PANTHER	PTHR10258. BK_channel_beta. 1 hit.
Pfam	PF03185. CaKB. 1 hit. [Graphical view]
PRINTS	PR01450. BKCHANNELB.
ProtoNet	Search...

Entry information

Entry name

KCMB1_BOVIN

Accession

Primary (citable) accession number: Q28067
Secondary accession number(s): A6QLJ1

Entry history

Integrated into UniProtKB/Swiss-Prot:	November 1, 1997
Last sequence update:	January 23, 2007
Last modified:	June 16, 2009
This is version 56 of the entry and version 3 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)