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Potassium channel subfamily M regulatory beta subunit 1
Symbols KCNMB1 ; BKbeta1; K(VCA)beta; SLO-BETA; hbeta1; hslo-beta; k(VCA)beta-1; slo-beta-1
External IDs OMIM603951 MGI1334203 HomoloGene3054 ChEMBL: 5078 GeneCards: KCNMB1 Gene
RNA expression pattern
PBB GE KCNMB1 209948 at tn.png
More reference expression data
Species Human Mouse
Entrez 3779 16533
Ensembl ENSG00000145936 ENSMUSG00000020155
UniProt Q16558 Q8CAE3
RefSeq (mRNA) NM_004137 NM_031169
RefSeq (protein) NP_004128 NP_112446
Location (UCSC) Chr 5:
170.37 – 170.39 Mb
Chr 11:
33.96 – 33.97 Mb
PubMed search [1] [2]

Calcium-activated potassium channel subunit beta-1 is a protein that in humans is encoded by the KCNMB1 gene.[1][2][3]


MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the product of this gene, the modulatory beta subunit. Intracellular calcium regulates the physical association between the alpha and beta subunits.[3] Beta subunits (beta 1-4) are highly tissue specific in their expression, with beta-1 being present predominantly on vascular smooth muscle. Endothelial cells are not known to express beta-1 subunits. Beta-1 is also known to be expressed in urinary bladder and in some regions of the brain. Association of the beta-1 subunit with the BK channel increases the apparent Ca2+ sensitivity of the channel and decreases voltage dependence.

See also[edit]


  1. ^ Tseng-Crank J, Godinot N, Johansen TE, Ahring PK, Strøbaek D, Mertz R, Foster CD, Olesen SP, Reinhart PH (Oct 1996). "Cloning, expression, and distribution of a Ca(2+)-activated K+ channel beta-subunit from human brain". Proc. Natl. Acad. Sci. U.S.A. 93 (17): 9200–5. doi:10.1073/pnas.93.17.9200. PMC 38619. PMID 8799178. 
  2. ^ Jiang Z, Wallner M, Meera P, Toro L (Mar 1999). "Human and rodent MaxiK channel beta-subunit genes: cloning and characterization". Genomics 55 (1): 57–67. doi:10.1006/geno.1998.5627. PMID 9888999. 
  3. ^ a b "Entrez Gene: KCNMB1 potassium large conductance calcium-activated channel, subfamily M, beta member 1". 

Further reading[edit]

This article incorporates text from the United States National Library of Medicine, which is in the public domain.