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 may partially inactivate or slightly decrease the activation time of MaxiK alpha subunit currents. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 22. [provided by RefSeq, Jul 2009]
Function:
MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels composed of the pore-forming alpha subunit and in some tissues a modulatory beta subunit. MaxiK cahannels are fundamental to the control of smooth muscle tone and neuronal excitability. KCNMB3 is a regulatory beta subunit of the MaxiK channel. It modulates the calcium sensitivity and gating kinetics of MaxiK thereby contributing to channel diversity.
Subcellular Location:
Membrane. Multi-pass membrane protein.
Tissue Specificity:
Isoform 1, isoform 3 and isoform 4 are widely expressed. Isoform 2 is expressed placenta, pancreas, kidney and heart. Isoform 1 and isoform 3 are highly expressed in pancreas and testis.
Post-translational modifications:
N-glycosylated.
The extracellular domain contains disulfide bond essential for the gating mechanism.
Similarity:
Belongs to the KCNMB (TC 8.A.14.1) family. KCNMB3 subfamily.
SWISS:
Q9NPA1
Gene ID:
27094
Database links:
Entrez Gene: 27094 Human
Entrez Gene: 435726 Mouse
Entrez Gene: 310303 Rat
Omim: 605222 Human
SwissProt: Q9NPA1 Human
SwissProt: A7VL23 Rat
Unigene: 591285 Human
Unigene: 218452 Rat
|
|
