Abstract
Ba2+ increases open probability and blocks the permeation pathway of BK channels. Here we discuss Cryo-EM structures of BK channels with Ba2+. They reveal that Ba2+ occupies site S3 in the selectivity filter, leading to blockade. Ba2+ are also detected at all high affinity Ca2+ binding sites of the gating ring. However, the architectures of this region in these structures represent intermediate transitions between the extreme close and open configurations.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Ba2+ increases open probability and blocks the permeation pathway of BK channels. Here we discuss Cryo-EM structures of BK channels with Ba2+. They reveal that Ba2+ occupies site S3 in the selectivity filter, leading to blockade. Ba2+ are also detected at all high affinity Ca2+ binding sites of the gating ring. However, the architectures of this region in these structures represent intermediate transitions between the extreme close and open configurations.