KCNMB1

Description

The KCNMB1 (potassium calcium-activated channel subfamily M regulatory beta subunit 1) is a protein-coding gene located on chromosome 5.

KCNMB1 (Calcium-activated potassium channel subunit beta-1) is a protein encoded by the KCNMB1 gene in humans. It plays a crucial role in regulating smooth muscle tone and neuronal excitability as part of maxiK channels. MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels, composed of two subunits: the pore-forming alpha subunit and the modulatory beta subunit encoded by KCNMB1. The association between the alpha and beta subunits is regulated by intracellular calcium. Beta subunits (beta 1-4) exhibit tissue-specific expression, with beta-1 predominantly found in vascular smooth muscle. Beta-1 is also present in urinary bladder and some brain regions. The association of the beta-1 subunit with the BK channel increases the apparent Ca2+ sensitivity of the channel and decreases voltage dependence.

KCNMB1, also known as BK channel subunit beta-1, is a regulatory subunit of the calcium-activated potassium channel KCNMA1 (maxiK). It modulates the calcium sensitivity and gating kinetics of KCNMA1, contributing to channel diversity. KCNMB1 increases the apparent Ca(2+)/voltage sensitivity of KCNMA1, slows down activation and deactivation kinetics, and alters pharmacological properties. It acts as a negative regulator of smooth muscle contraction by enhancing calcium sensitivity to KCNMA1. KCNMB1 is essential for internal binding of the KCNMA1 channel opener dehydrosoyasaponin I (DHS-1) and for external binding of the agonist hormone 17-beta-estradiol (E2). It also increases the binding activity of charybdotoxin (CTX) toxin to KCNMA1 by increasing the CTX association rate and decreasing the dissociation rate.

KCNMB1 is also known as BKbeta1, K(VCA)beta, SLO-BETA, hbeta1, hslo-beta, k(VCA)beta-1, slo-beta-1.

Associated Diseases

WES Whole Exome Sequencing

Clinical Exome Sequencing