KCNMB4

Potassium large conductance calcium-activated channel, subfamily M, beta member 4

Identifiers

External IDs

OMIM: 605223 MGI: 1913272 HomoloGene: 8721 GeneCards: KCNMB4 Gene

Gene ontology
Molecular function	• protein binding • calcium-activated potassium channel activity
Cellular component	• plasma membrane • integral component of plasma membrane • voltage-gated potassium channel complex
Biological process	• action potential • detection of calcium ion • potassium ion transport • synaptic transmission • blood coagulation • neuronal action potential • regulation of vasoconstriction • regulation of neurotransmitter secretion • potassium ion transmembrane transport
Sources: Amigo / QuickGO

RNA expression pattern

More reference expression data

Orthologs

Species

Human

Mouse

RefSeq (mRNA)

RefSeq (protein)

Location (UCSC)

Chr 12:
70.76 – 70.83 Mb

Chr 10:
116.42 – 116.47 Mb

PubMed search

Calcium-activated potassium channel subunit beta-4 is a protein that in humans is encoded by the KCNMB4 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 modulatory beta subunit. The protein encoded by this gene is an auxiliary beta subunit which slows activation kinetics, leads to steeper calcium sensitivity, and shifts the voltage range of current activation to more negative potentials than does the beta 1 subunit.^[3]

References

↑ Brenner R, Jegla TJ, Wickenden A, Liu Y, Aldrich RW (Apr 2000). "Cloning and functional characterization of novel large conductance calcium-activated potassium channel beta subunits, hKCNMB3 and hKCNMB4". J Biol Chem 275 (9): 6453–61. doi:10.1074/jbc.275.9.6453. PMID 10692449.
↑ Behrens R, Nolting A, Reimann F, Schwarz M, Waldschutz R, Pongs O (Jul 2000). "hKCNMB3 and hKCNMB4, cloning and characterization of two members of the large-conductance calcium-activated potassium channel beta subunit family". FEBS Lett 474 (1): 99–106. doi:10.1016/S0014-5793(00)01584-2. PMID 10828459.
↑ 3.0 3.1 "Entrez Gene: KCNMB4 potassium large conductance calcium-activated channel, subfamily M, beta member 4".

Orio P, Rojas P, Ferreira G, Latorre R (2002). "New disguises for an old channel: MaxiK channel beta-subunits.". News Physiol. Sci. 17: 156–61. PMID 12136044.
Liu QH, Williams DA, McManus C et al. (2000). "HIV-1 gp120 and chemokines activate ion channels in primary macrophages through CCR5 and CXCR4 stimulation". Proc. Natl. Acad. Sci. U.S.A. 97 (9): 4832–7. doi:10.1073/pnas.090521697. PMC 18318. PMID 10758170.
Meera P, Wallner M, Toro L (2000). "A neuronal β subunit (KCNMB4) makes the large conductance, voltage- and Ca2+-activated K+ channel resistant to charybdotoxin and iberiotoxin". Proc. Natl. Acad. Sci. U.S.A. 97 (10): 5562–7. doi:10.1073/pnas.100118597. PMC 25868. PMID 10792058.
Weiger TM, Holmqvist MH, Levitan IB et al. (2000). "A novel nervous system beta subunit that downregulates human large conductance calcium-dependent potassium channels". J. Neurosci. 20 (10): 3563–70. PMID 10804197.
Jin P, Weiger TM, Wu Y, Levitan IB (2002). "Phosphorylation-dependent functional coupling of hSlo calcium-dependent potassium channel and its hbeta 4 subunit". J. Biol. Chem. 277 (12): 10014–20. doi:10.1074/jbc.M107682200. PMID 11790768.
Jin P, Weiger TM, Levitan IB (2003). "Reciprocal modulation between the alpha and beta 4 subunits of hSlo calcium-dependent potassium channels". J. Biol. Chem. 277 (46): 43724–9. doi:10.1074/jbc.M205795200. PMID 12223479.
Strausberg RL, Feingold EA, Grouse LH et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932.
Gerhard DS, Wagner L, Feingold EA et al. (2004). "The Status, Quality, and Expansion of the NIH Full-Length cDNA Project: The Mammalian Gene Collection (MGC)". Genome Res. 14 (10B): 2121–7. doi:10.1101/gr.2596504. PMC 528928. PMID 15489334.

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

Membrane transport protein: ion channels (TC 1A)

Ca²⁺: Calcium channel

Ligand-gated	Inositol trisphosphate receptor 1 2 3 Ryanodine receptor 1 2 3

Voltage-gated	L-type/Ca_vα 1.1 1.2 1.3 1.4 N-type/Ca_vα2.2 P-type/Ca_vα 2.1 Q-type/Ca_vα2.1 R-type/Ca_vα2.3 T-type/Ca_vα 3.1 3.2 3.3 α₂δ-subunits 1 2 β-subunits β1 β2 β3 β4 γ-subunits γ1 γ2 γ3 γ4 Cation channels of sperm 1 2 3 4 Two-pore channel 1 2

Na⁺: Sodium channel

Constitutively active	Epithelial sodium channel α β γ δ

Proton-gated	Amiloride-sensitive cation channel 1 2 3 4

Voltage-gated	Na_vα 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 7A Na_vβ 1 2 3 4

K⁺: Potassium channel

Calcium-activated	BK channel α1 β1 β2 β3 β4 SK channel SK1 SK2 SK3 IK channel IK1 K_Ca 1.1 2.1 2.2 2.3 3.1 4.1 4.2 5.1

Inward-rectifier	K_ATP K_ir 1.1 2.1 2.2 2.3 2.4 2.6 GIRK/K_ir 3.1 3.2 3.3 3.4 K_ir 4.1 4.2 5.1 6.1 6.2 7.1

Tandem pore domain	K2P 1 2 3 4 5 6 7 9 10 12 13 15 16 17 18

Voltage-gated	K_vα1-6 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 2.1 2.2 3.1 3.2 3.3 3.4 4.1 4.2 4.3 5.1 6.1 6.2 6.3 6.4 K_vα7-12 7.1 7.2 7.3 7.4 7.5 8.1 8.2 9.1 9.2 9.3 10.1 10.2 11.1/hERG 11.2 11.3 12.1 12.2 12.3 K_vβ 1 2 3 KCNIP 1 2 3 4 minK/ISK minK/ISK-like MiRP 1 2 3 Shaker gene

Miscellaneous

Cl⁻: Chloride channel	Calcium-activated chloride channels Anoctamin ANO1 Bestrophin 1 2 Chloride Channel Accessory 1 2 3 4 CFTR CLCN 1 2 3 4 5 6 7 KA KB CLIC 1 2 3 4 5 6 L1 CLNS 1A 1B

H⁺: Proton channel	HVCN1

M⁺: CNG cation channel	α 1 2 3 4 β 1 2 3 HCN FC 1 2 3 4

M⁺: TRP cation channel	TRPA (1) TRPC 1 2 3 4 4AP 5 6 7 TRPM 1 2 3 4 5 6 7 8 TRPML 1 2 3 TRPN TRPP 1 2 TRPV 1 2 3 4 5 6

H₂O (+ solutes): Porin	Aquaporin 0 1 2 3 4 5 6 7 8 9 Voltage-dependent anion channel 1 2 3 General bacterial porin family

Cytoplasm: Gap junction	Connexin: A GJA1 GJA3 GJA4 GJA5 GJA8 GJA9 GJA10 B GJB1 GJB2 GJB3 GJB4 GJB5 GJB6 GJB7 C GJC1 GJC2 GJC3 D GJD2 GJD3 GJD4) Innexin

By gating mechanism

Ion channel class	Ligand-gated Light-gated Voltage-gated Stretch-activated

see also disorders

Index of cells

Description	Structure nucleus chromosome genetics Organelles peroxisome cytoskeleton centrosome epithelia cilia mitochondria Membranes proteins cell adhesions Membrane transport ion channels vesicular transport solute carrier ABC transporters ATPase oxidoreduction-driven

Disease	Structural peroxisome cytoskeleton cilia mitochondria nucleus scleroprotein Membrane channelopathy solute carrier ATPase ABC transporters other extracellular ligands cell surface receptors intracellular signalling Vesicular transport Pore-forming toxins

KCNMB4

See also

References

Further reading