Potassium calcium-activated channel subfamily M regulatory beta subunit 1 (KCNMB1)

KCNMB1 encodes the regulatory beta-1 subunit of the large conductance, calcium- and voltage-activated potassium (BK or MaxiK) channel. The beta-1 subunit is predominantly expressed in vascular smooth muscle and certain regions of the brain and bladder, where it is essential for coupling intracellular calcium signals to augmented channel activity and resultant vascular relaxation. Through modulating the BK channel's gating kinetics and calcium sensitivity, KCNMB1 plays a critical role in control of muscle contractility and membrane potential. Genetic variants, especially the E65K mutation, influence susceptibility to diastolic hypertension and have potential protective effects. Pharmacologically, KCNMB1 subunit presence alters drug responsiveness, notably increasing sensitivity to hormone (e.g., 17-beta-estradiol) and peptide (e.g., charybdotoxin) channel modulators.

Other names

Calcium-activated potassium channel subunit beta-1BK channel beta subunit 1MaxiK channel beta-subunit 1BKbeta1Slo-beta-1Charybdotoxin receptor subunit beta-1large conductance Ca2+-activated K+ channel beta 1 subunitBKbetahbeta1hslo-betaK(VCA)beta-1potassium large conductance calcium-activated channel, subfamily M, beta member 1K(VCA)betaSLO-BETA

Channel agonism (e.g., 17-beta-estradiol enhances channel activity via beta subunit); Channel antagonism/blocking (e.g., charybdotoxin binding affected by beta subunit); Modulation of calcium sensitivity and channel gating through beta subunit association