Structural basis for gating the high-conductance Ca²⁺-activated K⁺ channel.

ABSTRACT: The precise control of an ion channel gate by environmental stimuli is crucial for the fulfilment of its biological role. The gate in Slo1 K⁺ channels is regulated by two separate stimuli, intracellular Ca²⁺ concentration and membrane voltage. Slo1 is thus central to understanding the relationship between intracellular Ca²⁺ and membrane excitability. Here we present the Slo1 structure from Aplysia californica in the absence of Ca²⁺ and compare it with the Ca²⁺-bound channel. We show that Ca²⁺ binding at two unique binding sites per subunit stabilizes an expanded conformation of the Ca²⁺ sensor gating ring. These conformational changes are propagated from the gating ring to the pore through covalent linkers and thr

SUBMITTER: Hite RK 

PROVIDER: S-EPMC5513477 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature