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Updated: Jun 10, 2026

Mutagenesis and Functional Analysis of Ion Channels Heterologously Expressed in Mammalian Cells
Published on: October 1, 2010
BK channel activation: structural and functional insights
1Department of Biomedical Engineering and Cardiac Bioelectricity and Arrhythmia Center, Washington University, St. Louis, MO 63130, USA.
Abstract:
The voltage- and Ca(2+)-activated K(+) (BK) channels are involved in the regulation of neurotransmitter release and neuronal excitability. Structurally, BK channels are homologous to voltage- and ligand-gated K(+) channels, having a voltage sensor and pore as the membrane-spanning domain and a cytosolic domain containing metal binding sites. Recently published electron cryomicroscopy (cryo-EM) and X-ray crystallographic structures of the BK channel provided the first glimpse into the assembly of these domains, corroborating the close interactions among these domains during channel gating that have been suggested by functional studies. This review discusses these latest findings and an emerging new understanding about BK channel gating and implications for diseases such as epilepsy, in which mutations in BK channel genes have been associated.
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