Calcium-activated potassium channel subunit beta-1 is a protein that in humans is encoded by the KCNMB1gene.[5][6][7]
Function
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.[7] 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.[8]
Orio P, Rojas P, Ferreira G, Latorre R (Aug 2002). "New disguises for an old channel: MaxiK channel beta-subunits". News in Physiological Sciences. 17 (4): 156–61. doi:10.1152/nips.01387.2002. hdl:10533/173696. PMID12136044.
Gollasch M, Tank J, Luft FC, Jordan J, Maass P, Krasko C, Sharma AM, Busjahn A, Bähring S (May 2002). "The BK channel beta1 subunit gene is associated with human baroreflex and blood pressure regulation". Journal of Hypertension. 20 (5): 927–33. doi:10.1097/00004872-200205000-00028. PMID12011654. S2CID88440283.
Mazzone JN, Kaiser RA, Buxton IL (2003). "Calcium-activated potassium channel expression in human myometrium: effect of pregnancy". Proceedings of the Western Pharmacology Society. 45: 184–6. PMID12434576.
Kudlacek PE, Pluznick JL, Ma R, Padanilam B, Sansom SC (Aug 2003). "Role of hbeta1 in activation of human mesangial BK channels by cGMP kinase". American Journal of Physiology. Renal Physiology. 285 (2): F289-94. doi:10.1152/ajprenal.00046.2003. PMID12670831. S2CID3238002.
Ransom CB, Liu X, Sontheimer H (Jun 2003). "Current transients associated with BK channels in human glioma cells". The Journal of Membrane Biology. 193 (3): 201–13. doi:10.1007/s00232-003-2019-7. PMID12962281. S2CID20169684.