The steroid interaction site in transmembrane domain 2 of the large conductance, voltage- and calcium-gated potassium (BK) channel accessory β1 subunit.

ABSTRACT: Large conductance, voltage- and calcium-gated potassium (BK) channels regulate several physiological processes, including myogenic tone and thus, artery diameter. Nongenomic modulation of BK activity by steroids is increasingly recognized, but the precise location of steroid action remains unknown. We have shown that artery dilation by lithocholate (LC) and related cholane steroids is caused by a 2× increase in vascular myocyte BK activity (EC(50) = 45 μM), an action that requires β1 but not other (β2-β4) BK accessory subunits. Combining mutagenesis and patch-clamping under physiological conditions of calcium and voltage on BK α- (cbv1) and β1 subunits from rat cerebral artery myocytes, we identify the steroid interaction site from two regions in BK β1 transmembrane domain 2 proposed by co

SUBMITTER: Bukiya AN 

PROVIDER: S-EPMC3250185 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature