Send to

Choose Destination
Nature. 2017 Jan 5;541(7635):46-51. doi: 10.1038/nature20608. Epub 2016 Dec 14.

Cryo-EM structure of the open high-conductance Ca2+-activated K+ channel.

Author information

Rockefeller University and Howard Hughes Medical Institute, 1230 York Avenue, New York, New York 10065, USA.


The Ca2+-activated K+ channel, Slo1, has an unusually large conductance and contains a voltage sensor and multiple chemical sensors. Dual activation by membrane voltage and Ca2+ renders Slo1 central to processes that couple electrical signalling to Ca2+-mediated events such as muscle contraction and neuronal excitability. Here we present the cryo-electron microscopy structure of a full-length Slo1 channel from Aplysia californica in the presence of Ca2+ and Mg2+ at a resolution of 3.5 Å. The channel adopts an open conformation. Its voltage-sensor domain adopts a non-domain-swapped attachment to the pore and contacts the cytoplasmic Ca2+-binding domain from a neighbouring subunit. Unique structural features of the Slo1 voltage sensor suggest that it undergoes different conformational changes than other known voltage sensors. The structure reveals the molecular details of three distinct divalent cation-binding sites identified through electrophysiological studies of mutant Slo1 channels.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center